If you have an idea for a blog post or a new forum thread, then please contact us at forums@fqxi.org, with a summary of the topic and its source (e.g., an academic paper, conference talk, external blog post or news item).

Contests Home

Current Essay Contest

*Contest Partners: The Peter and Patricia Gruber Foundation and Scientific American*

Previous Contests

**How Should Humanity Steer the Future?**

*January 9, 2014 - August 31, 2014*

*Contest Partners: Jaan Tallinn, The Peter and Patricia Gruber Foundation, The John Templeton Foundation, and Scientific American*

read/discuss • winners

**It From Bit or Bit From It**

*March 25 - June 28, 2013*

*Contest Partners: The Gruber Foundation, J. Templeton Foundation, and Scientific American*

read/discuss • winners

**Questioning the Foundations**

Which of Our Basic Physical Assumptions Are Wrong?

*May 24 - August 31, 2012*

*Contest Partners: The Peter and Patricia Gruber Foundation, SubMeta, and Scientific American*

read/discuss • winners

**Is Reality Digital or Analog?**

*November 2010 - February 2011*

*Contest Partners: The Peter and Patricia Gruber Foundation and Scientific American*

read/discuss • winners

**What's Ultimately Possible in Physics?**

*May - October 2009*

*Contest Partners: Astrid and Bruce McWilliams*

read/discuss • winners

**The Nature of Time**

*August - December 2008*

read/discuss • winners

Current Essay Contest

Previous Contests

read/discuss • winners

read/discuss • winners

Which of Our Basic Physical Assumptions Are Wrong?

read/discuss • winners

read/discuss • winners

read/discuss • winners

read/discuss • winners

Forum Home

Introduction

Terms of Use

RSS feed | RSS help

Introduction

Terms of Use

*Posts by the author are highlighted in orange; posts by FQXi Members are highlighted in blue.*

RSS feed | RSS help

RECENT POSTS IN THIS TOPIC

**Author Yuri Danoyan+**: *on* 4/20/11 at 11:47am UTC, wrote Dear Daniele What is your prognoses about Fermilab experiment? ...

**Alan Lowey**: *on* 3/31/11 at 10:26am UTC, wrote Here's the next two pages..

**Alan Lowey**: *on* 3/31/11 at 10:26am UTC, wrote I've taken the liberty of scanning Professor Taylor's new book where he...

**Alan Lowey**: *on* 3/30/11 at 16:29pm UTC, wrote Hi Yuri, Yes, Professor Wintergerg has got it to a tee. Spot on. Sorry for...

**Author Yuri Danoyan+**: *on* 3/30/11 at 12:13pm UTC, wrote Gentlemens I wonder why you did not notice or do not want to notice the...

**Steve Dufourny**: *on* 3/26/11 at 11:21am UTC, wrote Ciao Daniele, You are welcome,sincerely. All the best. Steve

**Alan Lowey**: *on* 3/26/11 at 10:43am UTC, wrote Hello Daniele, I have another bugging question for you. I'm 100% convinced...

**Daniele Oriti**: *on* 3/25/11 at 23:46pm UTC, wrote Well, thanks a lot for reading it, and for your kind message. I am happy...

RECENT FORUM POSTS

**James Putnam**: "Georgina, Lets take your first point for this message: "Could you please..."
*in* Q&A with Paul Davies:...

**Steve Agnew**: "Yes, your various outlooks have a rather complex web of explanations. I..."
*in* Q&A with Paul Davies:...

**James Putnam**: ""It says the entropy (disorder) of a closed system always increases. " ..."
*in* The Quantum Thermodynamic...

**Pentcho Valev**: "The following argument is valid (although Einsteinians are unable to prove..."
*in* Indefinite Causality

**Steve Agnew**: "This sounds like a good Ph.D. project or a starter project, but why not go..."
*in* The Quantum Thermodynamic...

**Frank DiMeglio**: "It is clear that the BODILY/VISUAL experience of the eye is a CENTRAL POINT..."
*in* Ripping Apart Einstein

**Steve Agnew**: "The only thing that you enjoy more than exploring the deep rabbit holes..."
*in* Q&A with David Rideout:...

**James Putnam**: "Akinbo, You preceded your questions with: "You may need to clarify your..."
*in* Q&A with David Rideout:...

RECENT ARTICLES

*click titles to read articles*

**The Quantum Thermodynamic Revolution**

Combining theories of quantum information with the science of heat and energy transfer could lead to new technologies.

**Face Off: Building a Toy Universe to Pit Quantum Theory Against Gravity**

Using superconducting circuits to create a curved-spacetime analog with stronger gravity than our cosmos.

**Is Gravity Time's Archer?**

A new model argues the forces between particles in the early universe loosed time's arrow, creating temporal order from chaos.

**Purifying Physics: The Quest to Explain Why the “Quantum” Exists**

A new framework for the laws underlying reality could explain why nature obeys quantum rules, the origin of time’s arrow, and the power of quantum computing.

**Searching for the Impossible**

A quest to discover which computational tasks can never be resolved.

RECENT FORUM POSTS

RECENT ARTICLES

Combining theories of quantum information with the science of heat and energy transfer could lead to new technologies.

Using superconducting circuits to create a curved-spacetime analog with stronger gravity than our cosmos.

A new model argues the forces between particles in the early universe loosed time's arrow, creating temporal order from chaos.

A new framework for the laws underlying reality could explain why nature obeys quantum rules, the origin of time’s arrow, and the power of quantum computing.

A quest to discover which computational tasks can never be resolved.

FQXi FORUM

May 25, 2015

CATEGORY:
FQXi Essay Contest - Is Reality Digital or Analog?
[back]

TOPIC: On the Depth of Quantum Space by Daniele Oriti [refresh]

TOPIC: On the Depth of Quantum Space by Daniele Oriti [refresh]

We focus on the question: - Is space fundamentally discrete or continuous? - in the context of current quantum gravity research. In particular, we paint a scenario based on the idea that quantum space is a sort of peculiar condensed matter system, and on the speculation that its microscopic (atomic) dynamics is described by a group field theory formalism. We suggest that, from this perspective, on the one hand the question has no absolute meaning, so no answer, but also that, on the other hand, the reason why this is the case is the quantum space is much richer and more interesting than we may have assumed. We also speculate on further physical implications of the suggested scenario.

Born - Messina, Italy - Italian PhD - Univ Cambridge 2003 Postdoc - Univ Cambridge, Univ Utrecht, Perimerter Institute AEI senior researcher and leader of independent research group ''Microscopic Quantum Structure & Dynamics of Spacetime'' Sofja Kovalevskaja Prize awardee (A. Von Humboldt Foundation) (2008)

Dear Daniele ,

A very clearly written account of an interesting topic. You set out what you would be considering and the proceeded to do so in a way that smoothly carries the reader along. I did like the recurrence of the theme "it depends". You are so right it does depend. I came to the same conclusion at the end of my essay but you said it so much more clearly. The repetition not only tied the essay together but drove home how important that is. It is not a black or white question at all and the answer does depend in part on what is intended by the question when it is asked.

I do hope you get lots of interested readers who can give you feedback on the physics content. I think you did well to make this topic so accessible and educational to a non specialist and therefore enjoyable too.

Good luck, Georgina.

report post as inappropriate

A very clearly written account of an interesting topic. You set out what you would be considering and the proceeded to do so in a way that smoothly carries the reader along. I did like the recurrence of the theme "it depends". You are so right it does depend. I came to the same conclusion at the end of my essay but you said it so much more clearly. The repetition not only tied the essay together but drove home how important that is. It is not a black or white question at all and the answer does depend in part on what is intended by the question when it is asked.

I do hope you get lots of interested readers who can give you feedback on the physics content. I think you did well to make this topic so accessible and educational to a non specialist and therefore enjoyable too.

Good luck, Georgina.

report post as inappropriate

Hi Georgina,

thanks a lot for your kind words and appreciation. I will try to read as many a possible of the other essays submitted, and especially yours, and hope to have something interesting to say about it.

Thanks again.

D

report post as inappropriate

thanks a lot for your kind words and appreciation. I will try to read as many a possible of the other essays submitted, and especially yours, and hope to have something interesting to say about it.

Thanks again.

D

report post as inappropriate

Dear Daniele

My essay http://www.fqxi.org/community/forum/topic/946

contain some terahedron"s logic idea.Do you see something common with your triangles?

All the best

Yuri

report post as inappropriate

My essay http://www.fqxi.org/community/forum/topic/946

contain some terahedron"s logic idea.Do you see something common with your triangles?

All the best

Yuri

report post as inappropriate

Not really, at least at this point.

best,

Daniele

best,

Daniele

Dear Daniele,

I don't know of any physicist anymore in these days who would say that atoms are discrete ; isn't the main lesson of relativity that even the number of atoms is not well defined (and that the notion of particle itself is contextual)? Likewise, nobody would argue that a gas is somehow discrete and a fluid continuous merely because we can give such effective descriptions. Fact is that QFT is defined on a continuum (I know very well some version of it can be constructed on causal sets) and the whole rationale behind it comes from causality, locality, statistics, cluster decomposition and Poincare invariance. You adress none of these issues, neither do you indicate what group field theory can contribute to the status of them. Second, your comparison with condensed matter models is misleading since these are all background dependent; nobody knows how to recover a manifold structure in a background independent way since it requires local observables. The problem here is that you cannot define these in a canonical way. Moreover, you adress none of the philosophical problems of quantum spacetime (which actually make the whole idea rather unlikely).

So, I hope that you will say that the limitations of the contest format prohibited you from treating all these issues and that you can explain how you see them.

Kind regards,

Johan Noldus

report post as inappropriate

report post as inappropriate

report post as inappropriate

I don't know of any physicist anymore in these days who would say that atoms are discrete ; isn't the main lesson of relativity that even the number of atoms is not well defined (and that the notion of particle itself is contextual)? Likewise, nobody would argue that a gas is somehow discrete and a fluid continuous merely because we can give such effective descriptions. Fact is that QFT is defined on a continuum (I know very well some version of it can be constructed on causal sets) and the whole rationale behind it comes from causality, locality, statistics, cluster decomposition and Poincare invariance. You adress none of these issues, neither do you indicate what group field theory can contribute to the status of them. Second, your comparison with condensed matter models is misleading since these are all background dependent; nobody knows how to recover a manifold structure in a background independent way since it requires local observables. The problem here is that you cannot define these in a canonical way. Moreover, you adress none of the philosophical problems of quantum spacetime (which actually make the whole idea rather unlikely).

So, I hope that you will say that the limitations of the contest format prohibited you from treating all these issues and that you can explain how you see them.

Kind regards,

Johan Noldus

report post as inappropriate

Dear Johan,

thanks for you comments and interest, and sorry for the delay in my reply.

It is certainly true that the limitations of the essay format implied that I could not touch on all of the aspects of the problem that I would have like to, and that even those that I discussed could have been explained and treated in much more detail and more satisfactorily. However, it would not...

view entire post

thanks for you comments and interest, and sorry for the delay in my reply.

It is certainly true that the limitations of the essay format implied that I could not touch on all of the aspects of the problem that I would have like to, and that even those that I discussed could have been explained and treated in much more detail and more satisfactorily. However, it would not...

view entire post

report post as inappropriate

Dear Daniele,

The problem of quantum gravity is to give a description of nature which is in principle valid on all scales (this is by no means in contradiction with renormalization). So your answer that it depends upon the scale or system is unfortunately not valid. You seem to take the point of view that the observer(s) are somehow living in ''meta space'' and that the theory should...

view entire post

The problem of quantum gravity is to give a description of nature which is in principle valid on all scales (this is by no means in contradiction with renormalization). So your answer that it depends upon the scale or system is unfortunately not valid. You seem to take the point of view that the observer(s) are somehow living in ''meta space'' and that the theory should...

view entire post

report post as inappropriate

Dear Daniele,

Now that I see, I did not respond yet to a few points of yours. So, you admit the notion of a particle becomes superfluous in the context of relativity: therefore, why are you doing your best to reinstate this concept in a theory of quantum gravity?! Shouldn't you just do the opposite and move even further away (that is further weaken) from the concept of a particle than it is the case in QFT on Minkowski? Furthermore you imply that conditions like causality, positive energy and statistics are background dependent concepts... they are not by any means. You confuse the principle here with its implementation in QFT on Minkowski; actually, from the latter we know they are independent issues even in this weakened context. By this, I mean that, for example, one can drop positive energies and still get a causal QFT with the right statistics. If you think about it deeper, you will need a principle for having an arrow of time (positive energies) and independently you will need to specify the statistics (that is the very nature of quantum mechanics). Probably, you would need to specify the spin-statistics relation (all research to a spin statistics theorem in quantum gravity points in that direction) as well. So, you still need three independent principles and you haven't gained anything.

The problem is that you assume a priori that gravity has to be quantized like any ''particle'' does. You care to give a good physical motivation for this, apart from saying that ''quantum theory as we know it should be universally applicable?''.

Kind regards,

Johan

report post as inappropriate

Now that I see, I did not respond yet to a few points of yours. So, you admit the notion of a particle becomes superfluous in the context of relativity: therefore, why are you doing your best to reinstate this concept in a theory of quantum gravity?! Shouldn't you just do the opposite and move even further away (that is further weaken) from the concept of a particle than it is the case in QFT on Minkowski? Furthermore you imply that conditions like causality, positive energy and statistics are background dependent concepts... they are not by any means. You confuse the principle here with its implementation in QFT on Minkowski; actually, from the latter we know they are independent issues even in this weakened context. By this, I mean that, for example, one can drop positive energies and still get a causal QFT with the right statistics. If you think about it deeper, you will need a principle for having an arrow of time (positive energies) and independently you will need to specify the statistics (that is the very nature of quantum mechanics). Probably, you would need to specify the spin-statistics relation (all research to a spin statistics theorem in quantum gravity points in that direction) as well. So, you still need three independent principles and you haven't gained anything.

The problem is that you assume a priori that gravity has to be quantized like any ''particle'' does. You care to give a good physical motivation for this, apart from saying that ''quantum theory as we know it should be universally applicable?''.

Kind regards,

Johan

report post as inappropriate

Dear Danielle,

While reading your essay , I became very aware that I am not a professional scientist, but I understood very well your point of vieuw, which is very clear as you mention it in the end "IT DEPENDS".

In my simple vieuw it means that what you wrote does not yet give you a clear "yes" or "no" on the question, this of course is very understandable because I think that none of us has a ready, steady go explication of the fundamental questions of our existance and our universe. I even think you are very courageaous to admit that "it depends".

I am enjoying very much every essay in this contest, it means that our minds are looking for explications, the many vieuws distributed are for me like a rainbow , all promising coulours above a dark landscape, very encouraging.

We need the scientists and the cosmologists , the quantum physicians, the historians and the philosophers to make progress in our understanding, the danger however is that anyone who is a specialist forgets to stay in contact with other specialismes.

You mention in your essay singularities, for myself I wonder if these "ideas" are not only existing in our minds,and not in the "material reality" we are living in, what in fact is a point with no dimensions ? The Planck scale , is the ultimate border of our perceptance, the singularities you mention are also part of this area where all measurements are impossible, once accepting that singulairities only exist in our minds they no longer are subject of formula's and so we encounter less infinities, for that I like to mention my own contribution to this wonderfull thought process :

fqxi.org/community/forum/topic/913,

of course I have to admit that the consequences of my thoughts DEPEND on the basic assumptions but if we have no assumptions or beliefs we don't have to prove anything isn't it ?

I wish you also good luck with the contest.

kind regards

Wilhelmus de Wilde

report post as inappropriate

While reading your essay , I became very aware that I am not a professional scientist, but I understood very well your point of vieuw, which is very clear as you mention it in the end "IT DEPENDS".

In my simple vieuw it means that what you wrote does not yet give you a clear "yes" or "no" on the question, this of course is very understandable because I think that none of us has a ready, steady go explication of the fundamental questions of our existance and our universe. I even think you are very courageaous to admit that "it depends".

I am enjoying very much every essay in this contest, it means that our minds are looking for explications, the many vieuws distributed are for me like a rainbow , all promising coulours above a dark landscape, very encouraging.

We need the scientists and the cosmologists , the quantum physicians, the historians and the philosophers to make progress in our understanding, the danger however is that anyone who is a specialist forgets to stay in contact with other specialismes.

You mention in your essay singularities, for myself I wonder if these "ideas" are not only existing in our minds,and not in the "material reality" we are living in, what in fact is a point with no dimensions ? The Planck scale , is the ultimate border of our perceptance, the singularities you mention are also part of this area where all measurements are impossible, once accepting that singulairities only exist in our minds they no longer are subject of formula's and so we encounter less infinities, for that I like to mention my own contribution to this wonderfull thought process :

fqxi.org/community/forum/topic/913,

of course I have to admit that the consequences of my thoughts DEPEND on the basic assumptions but if we have no assumptions or beliefs we don't have to prove anything isn't it ?

I wish you also good luck with the contest.

kind regards

Wilhelmus de Wilde

report post as inappropriate

Dear Wilhelmus,

thanks for your kind comments.

Let me briefly reply on just one point about the intended meaning of my 'it depends'. It is not meant to simply state that ''we will never know for sure'', or that ''we do not know''. I agree with the latter of course, and not so much with the former statement. But it is not what I meant. What I meant is that the answer to the discrete/continuous question for quantum space can be possibly given exactly theoretically, and possibly even tested experimentally (being very speculative), but it will depend on the specific circumstances in which one poses it, in the same sense in which a similar question asked regarding a condensed matter system does. I gave some arguments for this view, offered some speculations, and pointed out that some recent work in quantum gravity has the potential to make the above a bit more precise. The position based on an 'it depends' of a different type, i.e. in which the precise conditions on which 'it depends' are not specified to some extent, would be at risk of being sterile.

Concerning singularities, indeed, several if not all practicing scientists believe the notion of singularity is but a label for a physical situation we do not understand yet, but not something physical in itself. However, the task is then to build up a theory of what happens in such situations, and unfortunately to simply deny their realities is not enough. We all have to be able to do better.

Thanks again and good luck to you as well!

report post as inappropriate

thanks for your kind comments.

Let me briefly reply on just one point about the intended meaning of my 'it depends'. It is not meant to simply state that ''we will never know for sure'', or that ''we do not know''. I agree with the latter of course, and not so much with the former statement. But it is not what I meant. What I meant is that the answer to the discrete/continuous question for quantum space can be possibly given exactly theoretically, and possibly even tested experimentally (being very speculative), but it will depend on the specific circumstances in which one poses it, in the same sense in which a similar question asked regarding a condensed matter system does. I gave some arguments for this view, offered some speculations, and pointed out that some recent work in quantum gravity has the potential to make the above a bit more precise. The position based on an 'it depends' of a different type, i.e. in which the precise conditions on which 'it depends' are not specified to some extent, would be at risk of being sterile.

Concerning singularities, indeed, several if not all practicing scientists believe the notion of singularity is but a label for a physical situation we do not understand yet, but not something physical in itself. However, the task is then to build up a theory of what happens in such situations, and unfortunately to simply deny their realities is not enough. We all have to be able to do better.

Thanks again and good luck to you as well!

report post as inappropriate

Danielle

Thank you for a very well written and comprehendable essay, exploring important territory in a clear and innovative way.

This has some interesting parallels with mine, which I hope you will be interested in reading to give you a different and very reality based perspective of the same territory (the string is also rich).

If you are able to increase the number of moving variables our brains can normally deal with I hope you might find it rewarding. I'd be interested in your response.

Very best of luck in the competition.

Peter

report post as inappropriate

Thank you for a very well written and comprehendable essay, exploring important territory in a clear and innovative way.

This has some interesting parallels with mine, which I hope you will be interested in reading to give you a different and very reality based perspective of the same territory (the string is also rich).

If you are able to increase the number of moving variables our brains can normally deal with I hope you might find it rewarding. I'd be interested in your response.

Very best of luck in the competition.

Peter

report post as inappropriate

Hi,

thanks for your kind words. Believe me, I would be indeed very happy if I was able to increase the number of variables my brain can deal with! :)

Best,

Daniele

report post as inappropriate

thanks for your kind words. Believe me, I would be indeed very happy if I was able to increase the number of variables my brain can deal with! :)

Best,

Daniele

report post as inappropriate

So, is quantum space continuous or discrete? If the above speculation is right, to

realize it concretely will be a revolutionary scientific and cultural experience. But it will not provide us with a better answer to this question than: “It depends”.

Daniele,

I love the above. It is cagey but true. My argument for analogue does not have your authority.

Jim Hoover

report post as inappropriate

realize it concretely will be a revolutionary scientific and cultural experience. But it will not provide us with a better answer to this question than: “It depends”.

Daniele,

I love the above. It is cagey but true. My argument for analogue does not have your authority.

Jim Hoover

report post as inappropriate

Dear Jim,

thanks a lot for your comment.

I do not know, of course, if I am right or wrong, and only further work will tell. I am sure of one thing only, though, that on this interesting and difficult matter, and at this stage of development, I have no authority whatsoever (as probably nobody else).

Thanks again.

Best,

Daniele

report post as inappropriate

thanks a lot for your comment.

I do not know, of course, if I am right or wrong, and only further work will tell. I am sure of one thing only, though, that on this interesting and difficult matter, and at this stage of development, I have no authority whatsoever (as probably nobody else).

Thanks again.

Best,

Daniele

report post as inappropriate

Why do you assume that probably nobody has ''authority'' in this kind of question? Moreover, what would you consider to be a satisfying answer ? If I tell you that local realism cannot be excluded by any experiment, would you say (a) that this is false (b) it is true (c) it is true, but not reasonable? Now suppose I would say that there is no good reason to abandon the continuum and that there exist strong arguments for it such as locality and local Lorentz covariance. Would you say then that (a) this might be true, but it doesn't prove that space-time is continuous since there is an extremely tiny possibility that my assumptions fail (b) this is true and probably means that space-time is a continuum (c) I exaggerate (and you explain why). Moreover, take now into account the ''failure'' of discrete space-time after 30 years and the impossibility of defining local observables for the gravitational field (even in classical gravity), how would you balance these facts?

To make myself crystal clear; suppose you have to bake a chicken and someone would actually make a fire and bake it on a plate, or someone else would put it on a plate and leave it in the sun holding a magnifying glass over it. Would you encourage the second option, knowing the benefits of the first?

Best,

Johan

report post as inappropriate

To make myself crystal clear; suppose you have to bake a chicken and someone would actually make a fire and bake it on a plate, or someone else would put it on a plate and leave it in the sun holding a magnifying glass over it. Would you encourage the second option, knowing the benefits of the first?

Best,

Johan

report post as inappropriate

>Why do you assume that probably nobody has ''authority'' in this kind of >question?

I simply mean that I am full of respect for anyone has studied carefully these issues (philosophical, mathematical, physical), thought hard about them, and understood already some aspects of them, but I am reluctant to grant 'authority' to anyone because 1) it is 'ideas' and 'results' that can have...

view entire post

I simply mean that I am full of respect for anyone has studied carefully these issues (philosophical, mathematical, physical), thought hard about them, and understood already some aspects of them, but I am reluctant to grant 'authority' to anyone because 1) it is 'ideas' and 'results' that can have...

view entire post

Dear Daniele,

I wanted to say hello and let you know how much I enjoyed reading your essay. I appreciated how it gave an understandable context for how a condensed matter system is analyzed starting from what is viewed at a macro level and nicely diving down into the details. I was uncertain if group field theory deals with the nucleus and the strong interaction. I thought your discussion was extremely relevant about what it might take to find a deeper explanation. Thanks for writing a very approachable and interesting essay.

Kind regards, Russell Jurgensen

report post as inappropriate

I wanted to say hello and let you know how much I enjoyed reading your essay. I appreciated how it gave an understandable context for how a condensed matter system is analyzed starting from what is viewed at a macro level and nicely diving down into the details. I was uncertain if group field theory deals with the nucleus and the strong interaction. I thought your discussion was extremely relevant about what it might take to find a deeper explanation. Thanks for writing a very approachable and interesting essay.

Kind regards, Russell Jurgensen

report post as inappropriate

Dear Russell, thanks for your very kind words. I take the opportunity you offer to comment briefly on whether GFTs do or can account also for nuclear physics, strong interactions and other matter dynamics. The very first thing to keep in mind is that GFTs as such are only recently receiving more attention, so

very few of these issues have been tackled. In particular, at the moment GFTs are studied and explored from the point of view of pure gravity, i.e. interpreted as models for quantum spacetime physics in absence of matter, encoding only the quantum gravitational degrees of freedom. Second, there are two (alternative?) points of view on how matter should be studied in this context. One is that one should add more degrees of freedom, more variables, those encoding matter fields, to the existing models, so to 'couple' matter to gravity, and then study the resulting coupled dynamics of both. In particular, one would then be interested in studying whether quantum gravity effects alter the dynamics of matter in a way that is falsifiable by experiments, or if quantum gravity helps in understanding better puzzling features of matter dynamics. Some models of GFT (and spin foam models) of gravity coupled to matter and gauge fields have been developed, but not much studied in their consequences yet. Another point of view is that matter fields and particles, and possibly also gauge fields, should not be added to the pure spacetime degrees of freedom, and one should not 'complicate' further existing quantum gravity models. Rather, this point of view goes, matter should 'emerge' from quantum spacetime dynamics itself, in some appropriate regime, a bit like excitations of a fluid, behaving indeed as scalar fields, emerge in the hydrodynamic description of it, from the same microscopic degrees of freedom that describe the fluid itself. If this point of view is correct, we should not make existing models more 'complete' or 'complicated, but rather learn first in what regime a description of space as a continuum is possible, and then how to 'extract' or identify, in this regime, the degrees of freedom that correspond to macroscopic gravity and those that correspond to other forces or particles. Needless to say, also this line of thought has been explored to some limited extent only recently, so it is early to say which alternative is more promising or successful. Clearly, how much and what GFTs have to say about the rest of physics, beside spacetime physics, depends a lot on which of these two perspectives one takes, as well as the mathematical and conceptual tools one decides to use similarly depend on this choice. We'll see.

Best,

Daniele

very few of these issues have been tackled. In particular, at the moment GFTs are studied and explored from the point of view of pure gravity, i.e. interpreted as models for quantum spacetime physics in absence of matter, encoding only the quantum gravitational degrees of freedom. Second, there are two (alternative?) points of view on how matter should be studied in this context. One is that one should add more degrees of freedom, more variables, those encoding matter fields, to the existing models, so to 'couple' matter to gravity, and then study the resulting coupled dynamics of both. In particular, one would then be interested in studying whether quantum gravity effects alter the dynamics of matter in a way that is falsifiable by experiments, or if quantum gravity helps in understanding better puzzling features of matter dynamics. Some models of GFT (and spin foam models) of gravity coupled to matter and gauge fields have been developed, but not much studied in their consequences yet. Another point of view is that matter fields and particles, and possibly also gauge fields, should not be added to the pure spacetime degrees of freedom, and one should not 'complicate' further existing quantum gravity models. Rather, this point of view goes, matter should 'emerge' from quantum spacetime dynamics itself, in some appropriate regime, a bit like excitations of a fluid, behaving indeed as scalar fields, emerge in the hydrodynamic description of it, from the same microscopic degrees of freedom that describe the fluid itself. If this point of view is correct, we should not make existing models more 'complete' or 'complicated, but rather learn first in what regime a description of space as a continuum is possible, and then how to 'extract' or identify, in this regime, the degrees of freedom that correspond to macroscopic gravity and those that correspond to other forces or particles. Needless to say, also this line of thought has been explored to some limited extent only recently, so it is early to say which alternative is more promising or successful. Clearly, how much and what GFTs have to say about the rest of physics, beside spacetime physics, depends a lot on which of these two perspectives one takes, as well as the mathematical and conceptual tools one decides to use similarly depend on this choice. We'll see.

Best,

Daniele

Dear Daniele, Thank you for your thoughtful reply and the solid approach you take towards analyzing models. I gave it a high rating. I realize there is only one day left, but I hope you will have a chance to read my essay that takes a different perspective to analyze a possible reason for particle energy.

Kind regards, Russell

report post as inappropriate

Kind regards, Russell

report post as inappropriate

Ciao Daniele,

Nice job! Indeed, one cannot even ponder a structure for space unless time (as in GR) is added. I like the way you get down to the nitty gritty of the topic. I have always admired Fotini Markopoulous's concept of geometrogenesis and I'm glad to see it getting more attention.

Thanks for this, and I hope you get a chance to visit my essay as well.

Best,

Tom

report post as inappropriate

Nice job! Indeed, one cannot even ponder a structure for space unless time (as in GR) is added. I like the way you get down to the nitty gritty of the topic. I have always admired Fotini Markopoulous's concept of geometrogenesis and I'm glad to see it getting more attention.

Thanks for this, and I hope you get a chance to visit my essay as well.

Best,

Tom

report post as inappropriate

Dear Tom, thanks for your interest and appreciation. I am trying to read as many essays as possible, so I am looking forward to read yours. I am indeed enjoying a lot the melting pot of ideas and perspectives offered by such a variety of contributors. Regarding your mention of the 'geometrogenesis' idea, I find it indeed very fascinating. I find it interesting and fascinating first of all in the terms and context (quantum graphity) in which the name has been first proposed, by Fotini and others, as a (phase) transition from a discrete 'proto-spacetime' discrete structure to another, still discrete structure in which one can however see already some basic spacetime notions as applicable, like locality or dimension. But also, I am attracted by the broader idea of spacetime and geometry as emerging from a sort of phase transition, and possibly involving also a discrete-coninuum transition, from 'something' that cannot be interpreted in spacetime terms. In this broader sense, the idea is of course much older, and has been explored to some extent in other approaches like discrete gravity (Regge calculus, dynamical triangulations, causal sets, etc). Also, a scenario of this type has been considered, even if maybe not explored in too concrete terms, in analog gravity models in condensed matter, as well as put forward in a cosmological context. It is indeed, I think, cool stuff!

ciao

Daniele

ciao

Daniele

Daniele, it is good to see you in this contest and doing well. I have admired the group field theory approach since its origins with people such as Boulatov. I mentioned it in my review if discrete space-time concepts back in arXiv:hep-th/9506171. I am pleased that you and your colleagues are keeping the idea alive and continuing to develop it.

As you say geometrogenesis goes back a long way. For example I discussed very similar ideas in arXiv:hep-th/9505089 but did not come up with such a great name or concrete realization. Even earlier forms of similar work are mentioned in my review. Fotini Markopoulous has done a great job of making the concepts much clearer in the context of quantum graphity. It would be be a big development if such phase transitions could be found in relation to a more mathematically rich approach such as group field theory. Do you see any indications of this being possible?

report post as inappropriate

As you say geometrogenesis goes back a long way. For example I discussed very similar ideas in arXiv:hep-th/9505089 but did not come up with such a great name or concrete realization. Even earlier forms of similar work are mentioned in my review. Fotini Markopoulous has done a great job of making the concepts much clearer in the context of quantum graphity. It would be be a big development if such phase transitions could be found in relation to a more mathematically rich approach such as group field theory. Do you see any indications of this being possible?

report post as inappropriate

Hi Philip

Thanks a lot for your encouraging comments, and for the useful references. I do have indications that this type of phase transitions can be realized also in complex models like GFTs, although of course they are indirect indications and indications only. One example is that of matrix models for 2d gravity, where exactly something like this happens and which are in both conceptual and mathematical terms the (very successful) precursors of GFTs. We even have very preliminary work in this direction, but it is way to early to say whether our results will hold after further scrutiny and development.

Best,

Daniele

Thanks a lot for your encouraging comments, and for the useful references. I do have indications that this type of phase transitions can be realized also in complex models like GFTs, although of course they are indirect indications and indications only. One example is that of matrix models for 2d gravity, where exactly something like this happens and which are in both conceptual and mathematical terms the (very successful) precursors of GFTs. We even have very preliminary work in this direction, but it is way to early to say whether our results will hold after further scrutiny and development.

Best,

Daniele

Dear Daniele Oriti

As generally it bother me at all contestants that Zeilinger-Brukner theory of atomization of information is not mentioned here. Feynman also mentioned similarly as they. So the essence is in discrete world. Almost obvious existence of Planck's space-time shows similarly. It would be well, that all contestants should mentioned this - I think on proponents and opponents of digital physical world. I have not read all essays, does anyone mentioned this?

It is a general argument (also yours) that quantum field theory is continuous, and that field is more important than particles. But we should not ignore that final version of QFT is in discrete Planck's space.

You mentioned richness of those models. But we should be aware that there is also richness of possibility of simple models. It is expected that quantum gravity should be a simple theory. You gave a comparison with condensed matter. This can be also a rich topic, but this is not necessary for foundations of this. And, foundations of condensed matter and quantum gravity are different.

You mentioned that you begin with quantization of space. It should be well to mention that space-time without matter does not exist, so this is a quantization of matter. (But from your graphs it seems, that this is your standpoint.)

You mentioned that wave function exists in a every node. It seem to me, that wave function is only a thing of continuous space. I speculate this after reading Brukner-Zeilinger interpretation (quant-ph/0212084).

I was late for this contest, so my ideas can be read here. http://vixra.org/pdf/1103.0025v1.pdf

I have also an article, which is not speculative and it is a base for the above article. http://vixra.org/pdf/1012.0006v3.pdf There are also additional claims about connections between matter and space-time. I need someone who will be the arxiv endorser for this article. So that I will get opportunity, that my theories will be discussed.

Best regards

Janko Kokosar

report post as inappropriate

As generally it bother me at all contestants that Zeilinger-Brukner theory of atomization of information is not mentioned here. Feynman also mentioned similarly as they. So the essence is in discrete world. Almost obvious existence of Planck's space-time shows similarly. It would be well, that all contestants should mentioned this - I think on proponents and opponents of digital physical world. I have not read all essays, does anyone mentioned this?

It is a general argument (also yours) that quantum field theory is continuous, and that field is more important than particles. But we should not ignore that final version of QFT is in discrete Planck's space.

You mentioned richness of those models. But we should be aware that there is also richness of possibility of simple models. It is expected that quantum gravity should be a simple theory. You gave a comparison with condensed matter. This can be also a rich topic, but this is not necessary for foundations of this. And, foundations of condensed matter and quantum gravity are different.

You mentioned that you begin with quantization of space. It should be well to mention that space-time without matter does not exist, so this is a quantization of matter. (But from your graphs it seems, that this is your standpoint.)

You mentioned that wave function exists in a every node. It seem to me, that wave function is only a thing of continuous space. I speculate this after reading Brukner-Zeilinger interpretation (quant-ph/0212084).

I was late for this contest, so my ideas can be read here. http://vixra.org/pdf/1103.0025v1.pdf

I have also an article, which is not speculative and it is a base for the above article. http://vixra.org/pdf/1012.0006v3.pdf There are also additional claims about connections between matter and space-time. I need someone who will be the arxiv endorser for this article. So that I will get opportunity, that my theories will be discussed.

Best regards

Janko Kokosar

report post as inappropriate

Dear Janko,

Thanks for your interest and comments. I reply to some of them below.

>As generally it bother me at all contestants that Zeilinger-Brukner theory

>of atomization of information is not mentioned here. Feynman also

>mentioned similarly as they. So the essence is in discrete world. Almost >obvious existence of Planck's space-time shows similarly....

view entire post

Thanks for your interest and comments. I reply to some of them below.

>As generally it bother me at all contestants that Zeilinger-Brukner theory

>of atomization of information is not mentioned here. Feynman also

>mentioned similarly as they. So the essence is in discrete world. Almost >obvious existence of Planck's space-time shows similarly....

view entire post

Dear Daniele,

I really appreciated your essay which bring very interesting and innovative ideas while still being of perfectly scientific level. I share your view of the cosmological phase transition instead of a big bang. My own work totally agree with that thesis. Quantum space is now crystallized (as an hyperdiamond) and should have emerged from a liquid or gaseous phase. It is made of a trivalent graph, evolving through pachner moves, and quantized as spin foam. The crystallographic structure embed standard model through e8 roots.

Best regards

Ray

report post as inappropriate

I really appreciated your essay which bring very interesting and innovative ideas while still being of perfectly scientific level. I share your view of the cosmological phase transition instead of a big bang. My own work totally agree with that thesis. Quantum space is now crystallized (as an hyperdiamond) and should have emerged from a liquid or gaseous phase. It is made of a trivalent graph, evolving through pachner moves, and quantized as spin foam. The crystallographic structure embed standard model through e8 roots.

Best regards

Ray

report post as inappropriate

Hi,

thanks a lot. I am happy to see that similar ideas are shared by people coming from different paths. It can still be we are all wrong, of course, but at least it serves as an encouragement to keep working.

Best,

Daniele

report post as inappropriate

thanks a lot. I am happy to see that similar ideas are shared by people coming from different paths. It can still be we are all wrong, of course, but at least it serves as an encouragement to keep working.

Best,

Daniele

report post as inappropriate

Dear Daniele,

As a first comment, you seem to confuse my certainty about what does not work with the attitude that I know how it works. Maybe even this last statement is true, but that remains to be seen; in contrast to you, I am not justifying my own shortcomings by relating them to the weaknesses of others.

In the first paragraph you say nothing I disagree with, the point I...

view entire post

As a first comment, you seem to confuse my certainty about what does not work with the attitude that I know how it works. Maybe even this last statement is true, but that remains to be seen; in contrast to you, I am not justifying my own shortcomings by relating them to the weaknesses of others.

In the first paragraph you say nothing I disagree with, the point I...

view entire post

report post as inappropriate

>As a first comment, you seem to confuse my certainty about what does not >work with the attitude that I know how it works. Maybe even this last

even this type of certainty is something I quite envy. I am not certain even about the incorrectness of any of the many approaches to quantum gravity I know of. Obviously, I have my own preferences, which I try to base as much as I can on...

view entire post

even this type of certainty is something I quite envy. I am not certain even about the incorrectness of any of the many approaches to quantum gravity I know of. Obviously, I have my own preferences, which I try to base as much as I can on...

view entire post

Dear Daniele,

To respond to your second mail, yes you do reinstate ''particles'' by considering discrete chunks of ''space-time''. Concerning causality, you indeed do not understand what I say. Even in quantum field theories on a background space-time you have two different notions. First you have the light-cones which give you a distinction between what we call future and past (as well as the conformal scale) and second you have the Heisenberg commutation relations. One question is whether these two notions should coincide even for interacting quantum theories on Minkowski. But that was not my point. Nobody knows what causality means in the context of quantum gravity (even not Rafael Sorkin) and the point I made was that it should not be a fundamental principle here. This means that you have to modify somehow quantum mechanics itself unless you want to break local Lorentz covariance.

Second, the notion of energy is indeed thight to timelike isometries in the conventional way of thinking. That is why the conventional way of thinking is wrong (and again you will find an answer to this in my little paper). Third statistics has nothing to do with the wave function, it is a the heart of quantum theory itself; it actually determines the dynamics ! Even more than this, the statistics question is only well posed on Minkowski because swapping free particles there is physically a well defined and path independent operation. The question itself even doesn't make any sense in a curved space-time (even one with a killing symmetry). So what I say is that QFT is even wrong in these cases. The controversy here is that all these principles are the corner stones of quantum theory itself and your favorite approaches leave quantum mechanics itself virtually untouched. That cannot be if you imagine the substitute principles to be very different.

Kind regards,

Johan

report post as inappropriate

To respond to your second mail, yes you do reinstate ''particles'' by considering discrete chunks of ''space-time''. Concerning causality, you indeed do not understand what I say. Even in quantum field theories on a background space-time you have two different notions. First you have the light-cones which give you a distinction between what we call future and past (as well as the conformal scale) and second you have the Heisenberg commutation relations. One question is whether these two notions should coincide even for interacting quantum theories on Minkowski. But that was not my point. Nobody knows what causality means in the context of quantum gravity (even not Rafael Sorkin) and the point I made was that it should not be a fundamental principle here. This means that you have to modify somehow quantum mechanics itself unless you want to break local Lorentz covariance.

Second, the notion of energy is indeed thight to timelike isometries in the conventional way of thinking. That is why the conventional way of thinking is wrong (and again you will find an answer to this in my little paper). Third statistics has nothing to do with the wave function, it is a the heart of quantum theory itself; it actually determines the dynamics ! Even more than this, the statistics question is only well posed on Minkowski because swapping free particles there is physically a well defined and path independent operation. The question itself even doesn't make any sense in a curved space-time (even one with a killing symmetry). So what I say is that QFT is even wrong in these cases. The controversy here is that all these principles are the corner stones of quantum theory itself and your favorite approaches leave quantum mechanics itself virtually untouched. That cannot be if you imagine the substitute principles to be very different.

Kind regards,

Johan

report post as inappropriate

>To respond to your second mail, yes you do reinstate ''particles'' by >considering discrete chunks of ''space-time''.

as an analogy, indeed. But as such it does not contradict anything we know about existence or non-existence, validity or not validity of the particle concept, in flat or curved spaces etc.

>Nobody knows what causality means in the context of quantum gravity...

view entire post

as an analogy, indeed. But as such it does not contradict anything we know about existence or non-existence, validity or not validity of the particle concept, in flat or curved spaces etc.

>Nobody knows what causality means in the context of quantum gravity...

view entire post

Dear Daniele,

I start to doubt whether you understand the basics of science. No idea can be proven wrong, a concrete realization can but the principle itself not. The whole scientific enterprise consists of the delicate art of balancing between principles, representations, ontology and experiment. For example, in case of Bell's theorem, most people would say it excludes local realism assuming the experiments favor quantum predictions but this is manifestly false, strictly speaking. Morally, however, I think it is true; by this I mean that a local realist theory matching nature would not be very natural and complicated.

Furthermore, you do not seem to realize the depth of locality and local poincare invariance as fundamental principles of nature (which leads to the continuum). Both are tied to the definition of the vacuum state, something your favorite approaches fail in.

Third, no, by failure I meant failure of discrete approaches. We are actually almost nowhere yet. Nobody knows how to properly construct a smooth effective geometry from a discrete spaghetti, nobody knows even to define the equivalent of a d'Alembertian on random discrete structures and so on... These are merely questions one should try to understand on the kinematical level first and all these difficulties are not present in the continuum approach. I guess you haven't thought too much about these things.

About chickens, there exist plenty of possibilities: either you don't understand what the animal is, or you have prejudices about what it should be. Or perhaps, your palet is not as refined as one would expect it to be from an italian. Anyway, if you do not go and look for the chicken itself and keep on waiting, chances are high you will eat an earthworm in the end.

Kind regards,

Johan

report post as inappropriate

I start to doubt whether you understand the basics of science. No idea can be proven wrong, a concrete realization can but the principle itself not. The whole scientific enterprise consists of the delicate art of balancing between principles, representations, ontology and experiment. For example, in case of Bell's theorem, most people would say it excludes local realism assuming the experiments favor quantum predictions but this is manifestly false, strictly speaking. Morally, however, I think it is true; by this I mean that a local realist theory matching nature would not be very natural and complicated.

Furthermore, you do not seem to realize the depth of locality and local poincare invariance as fundamental principles of nature (which leads to the continuum). Both are tied to the definition of the vacuum state, something your favorite approaches fail in.

Third, no, by failure I meant failure of discrete approaches. We are actually almost nowhere yet. Nobody knows how to properly construct a smooth effective geometry from a discrete spaghetti, nobody knows even to define the equivalent of a d'Alembertian on random discrete structures and so on... These are merely questions one should try to understand on the kinematical level first and all these difficulties are not present in the continuum approach. I guess you haven't thought too much about these things.

About chickens, there exist plenty of possibilities: either you don't understand what the animal is, or you have prejudices about what it should be. Or perhaps, your palet is not as refined as one would expect it to be from an italian. Anyway, if you do not go and look for the chicken itself and keep on waiting, chances are high you will eat an earthworm in the end.

Kind regards,

Johan

report post as inappropriate

>I start to doubt whether you understand the basics of science.

I see you are not able to avoid personal statements. That is bad. But I think I can still manage to do so, which is good because they are not very useful.

>No idea can be proven wrong, a concrete realization can but the principle >itself not. The whole scientific enterprise consists of the delicate art >of balancing between principles, representations, ontology and experiment.

Thanks for this brief summary of the last centuries of philosophical thinking.

>Furthermore, you do not seem to realize the depth of locality and local >poincare invariance as fundamental principles of nature (which leads to >the continuum). Both are tied to the definition of the vacuum state, >something your favorite approaches fail in.

it could well be that I fail to appreciate fully these principles. However, I have been working also on identifying the basic symmetries and the correct notion of locality that applies, in absence of a background spacetime, to the kind of models I like, and how these characterize the GFT (perturbative) vacuum state. It must mean that I somehow sense, in all my limitations, the importance of them, for any physical theory.

>Third, no, by failure I meant failure of discrete approaches. We are >actually almost nowhere yet. Nobody knows how to properly construct a >smooth effective geometry from a discrete spaghetti, nobody knows even to >define the equivalent of a d'Alembertian on random discrete structures and >so on... These are merely questions one should try to understand on the >kinematical level first and all these difficulties are not present in the >continuum approach. I guess you haven't thought too much about these >things.

Beside once more irrelevant personal statements, I guess I disagree on the evaluation of what we have achieved and understood, up to now, in the different continuum and discrete approaches to quantum gravity. Never mind. There are plenty of clever people I disagree with and others I agree with.

>About chickens, there exist plenty of possibilities: either you don't >understand what the animal is, or you have prejudices about what it should >be. Or perhaps, your palet is not as refined as one would expect it to be >from an italian. Anyway, if you do not go and look for the chicken itself >and keep on waiting, chances are high you will eat an earthworm in the >end.

I agree with all of the above, if you meant it as a general statement; I still fail to appreciate it, if you intended it as referring to me personally.

Now, please excuse me....I have a chicken in the oven....

I see you are not able to avoid personal statements. That is bad. But I think I can still manage to do so, which is good because they are not very useful.

>No idea can be proven wrong, a concrete realization can but the principle >itself not. The whole scientific enterprise consists of the delicate art >of balancing between principles, representations, ontology and experiment.

Thanks for this brief summary of the last centuries of philosophical thinking.

>Furthermore, you do not seem to realize the depth of locality and local >poincare invariance as fundamental principles of nature (which leads to >the continuum). Both are tied to the definition of the vacuum state, >something your favorite approaches fail in.

it could well be that I fail to appreciate fully these principles. However, I have been working also on identifying the basic symmetries and the correct notion of locality that applies, in absence of a background spacetime, to the kind of models I like, and how these characterize the GFT (perturbative) vacuum state. It must mean that I somehow sense, in all my limitations, the importance of them, for any physical theory.

>Third, no, by failure I meant failure of discrete approaches. We are >actually almost nowhere yet. Nobody knows how to properly construct a >smooth effective geometry from a discrete spaghetti, nobody knows even to >define the equivalent of a d'Alembertian on random discrete structures and >so on... These are merely questions one should try to understand on the >kinematical level first and all these difficulties are not present in the >continuum approach. I guess you haven't thought too much about these >things.

Beside once more irrelevant personal statements, I guess I disagree on the evaluation of what we have achieved and understood, up to now, in the different continuum and discrete approaches to quantum gravity. Never mind. There are plenty of clever people I disagree with and others I agree with.

>About chickens, there exist plenty of possibilities: either you don't >understand what the animal is, or you have prejudices about what it should >be. Or perhaps, your palet is not as refined as one would expect it to be >from an italian. Anyway, if you do not go and look for the chicken itself >and keep on waiting, chances are high you will eat an earthworm in the >end.

I agree with all of the above, if you meant it as a general statement; I still fail to appreciate it, if you intended it as referring to me personally.

Now, please excuse me....I have a chicken in the oven....

Hi Daniele. I used the opportunity of this essay competition to write what I feel is the burden of proof for all condensed matter models where Lorentz invariance is emergent, which are presumably rich enough to include the standard model matter content. If you are interested it is here

http://www.fqxi.org/community/forum/topic/856

I am curious about your thoughts, either in the context of your model, or in general.

Best,

Moshe

report post as inappropriate

http://www.fqxi.org/community/forum/topic/856

I am curious about your thoughts, either in the context of your model, or in general.

Best,

Moshe

report post as inappropriate

Hi Moshe,

thanks for your message and interest. I had already downloaded your essay, of course, but I didn't manage to read it yet. I hope t be able to do it by tomorrow.

If I have anything interesting to say, I'll send you my comments.

Best,

Daniele

thanks for your message and interest. I had already downloaded your essay, of course, but I didn't manage to read it yet. I hope t be able to do it by tomorrow.

If I have anything interesting to say, I'll send you my comments.

Best,

Daniele

Hi Moshe,

I managed to read your essay and liked it a lot. I won't manage to write you an appropriate reply to the various issues you raise now, but I'll try to do it (either here or in private) as soon as possible. There are several points I would like to make on them, some partial answers and some more confusion to share, but it takes some time. At least, I managed to vote for your essay!

Thanks again.

Daniele

I managed to read your essay and liked it a lot. I won't manage to write you an appropriate reply to the various issues you raise now, but I'll try to do it (either here or in private) as soon as possible. There are several points I would like to make on them, some partial answers and some more confusion to share, but it takes some time. At least, I managed to vote for your essay!

Thanks again.

Daniele

Dear Daniele,

Regarding your first reply, you still seem to deny my statement that what you say is not relevant as an answer to the contest; I do not see why you don't because many people I know do understand so.

Concerning your classical boundaries in a ''partially quantum universe'', I do not see any logical reasoning behind it apart from the desire to have classical boundary structures in order to define observables. For example, how large are these chunks, what physical principle decides upon that ? Moreover, for ordinary particle theory in curved spacetime, no such boundaries are present (and would destroy the coherence of the theory) except at asymptotic infinity which is held flat or de Sitter.

Third, the inclusion of matter needs to break general covariance in one of the following senses:

(a) either you have a diffeomorphism invariant dynamics (that is a new constraint algebra containing the matter variables) but you have to resort to partial observables.

(b) the quantization of gravity with matter will induce anomalies in the algebra.

Concerning the constraint algebra, this question has not even been settled in pure gravity theory because the quantization procedure treats the Hamiltonian different from the spacelike diffeomorphism constraints. Concerning (a), this is physically nonsensical because I do not see how you would retrieve an arrow of time in this way.

Fourth, I did not say that pure gravity was ill defined, I simply said it has no observables; it is an empty theory from the physical point of view, while the limit of zero gravity is not and that is actually the correct vacuum.

Fifth, I do not know of any standard approach to quantum theory which is not grounded in a classical theory. The path integral approach has the classical action as starting point and likewise so for the Hamiltonian one. The only kind of reasoning which departs from quantum concepts partially (but not fully) can be found in the book of Weinberg.

Asymptotic freedom is just the physical idea that on short distance scales the theory becomes a free one. This is a well defined concept in a quantum as well as classical setting.

Finally, relativity was found by reasoning in terms of a new principle. Einstein clearly thought about general covariance and there exist plenty of historical documents to prove that. I am not sure about the person, but I remember he told to Planck about a generally covariant law for gravitation and the response was that nobody would be interested in that.

Moreover, you completely miss the point that finding principles is very difficult because it implies that your really know what you are doing physically.

Kind regards,

Johan

report post as inappropriate

report post as inappropriate

Regarding your first reply, you still seem to deny my statement that what you say is not relevant as an answer to the contest; I do not see why you don't because many people I know do understand so.

Concerning your classical boundaries in a ''partially quantum universe'', I do not see any logical reasoning behind it apart from the desire to have classical boundary structures in order to define observables. For example, how large are these chunks, what physical principle decides upon that ? Moreover, for ordinary particle theory in curved spacetime, no such boundaries are present (and would destroy the coherence of the theory) except at asymptotic infinity which is held flat or de Sitter.

Third, the inclusion of matter needs to break general covariance in one of the following senses:

(a) either you have a diffeomorphism invariant dynamics (that is a new constraint algebra containing the matter variables) but you have to resort to partial observables.

(b) the quantization of gravity with matter will induce anomalies in the algebra.

Concerning the constraint algebra, this question has not even been settled in pure gravity theory because the quantization procedure treats the Hamiltonian different from the spacelike diffeomorphism constraints. Concerning (a), this is physically nonsensical because I do not see how you would retrieve an arrow of time in this way.

Fourth, I did not say that pure gravity was ill defined, I simply said it has no observables; it is an empty theory from the physical point of view, while the limit of zero gravity is not and that is actually the correct vacuum.

Fifth, I do not know of any standard approach to quantum theory which is not grounded in a classical theory. The path integral approach has the classical action as starting point and likewise so for the Hamiltonian one. The only kind of reasoning which departs from quantum concepts partially (but not fully) can be found in the book of Weinberg.

Asymptotic freedom is just the physical idea that on short distance scales the theory becomes a free one. This is a well defined concept in a quantum as well as classical setting.

Finally, relativity was found by reasoning in terms of a new principle. Einstein clearly thought about general covariance and there exist plenty of historical documents to prove that. I am not sure about the person, but I remember he told to Planck about a generally covariant law for gravitation and the response was that nobody would be interested in that.

Moreover, you completely miss the point that finding principles is very difficult because it implies that your really know what you are doing physically.

Kind regards,

Johan

report post as inappropriate

>Concerning your classical boundaries in a ''partially quantum universe'', I do not see any logical reasoning behind it apart

>from the desire to have classical boundary structures in order to define observables. For example, how large are these chunks,

>what physical principle decides upon that ? Moreover, for ordinary particle theory in curved spacetime, no such...

view entire post

>from the desire to have classical boundary structures in order to define observables. For example, how large are these chunks,

>what physical principle decides upon that ? Moreover, for ordinary particle theory in curved spacetime, no such...

view entire post

report post as inappropriate

Dear Daniele,

Concerning your second mail, I will only mention the points I think are wrong. The deformations of the Lorentz group do break Lorentz invariance at high energies, that is why we call it a deformation. All these type of ideas are ad hoc and lack foundational insight. Moreover, the representation theory of these deformed Lorentz groups has still to be developed so that we obtain a new non commutative space-time picture; we are still nowhere near that. So what I would like to see is a new set of physical priniples; the Poincare group is derived from continuum, homogeneity, isotropy and causality of the vacuum. Therefore, if you think the Poincare algebra is a piece of shit because you are overpowered by renormalization problems, tell me which one of these principles fails and what type of new symmetry structures you will recover. I doubt whether these structures have anything to do with Hopf algebra's.

Concerning your comments about quantum mechanics, we need much more than just a reinterpretation, if it were only that simple. We need new mathematical structures, and no they are fairly unique and not fexible at all.

Best,

Johan

report post as inappropriate

Concerning your second mail, I will only mention the points I think are wrong. The deformations of the Lorentz group do break Lorentz invariance at high energies, that is why we call it a deformation. All these type of ideas are ad hoc and lack foundational insight. Moreover, the representation theory of these deformed Lorentz groups has still to be developed so that we obtain a new non commutative space-time picture; we are still nowhere near that. So what I would like to see is a new set of physical priniples; the Poincare group is derived from continuum, homogeneity, isotropy and causality of the vacuum. Therefore, if you think the Poincare algebra is a piece of shit because you are overpowered by renormalization problems, tell me which one of these principles fails and what type of new symmetry structures you will recover. I doubt whether these structures have anything to do with Hopf algebra's.

Concerning your comments about quantum mechanics, we need much more than just a reinterpretation, if it were only that simple. We need new mathematical structures, and no they are fairly unique and not fexible at all.

Best,

Johan

report post as inappropriate

>Concerning your second mail, I will only mention the points I think are wrong. The deformations of the Lorentz group do break

>Lorentz invariance at high energies, that is why we call it a deformation.

This is false. Any deformation of the Lorentz (or Poincare) algebra I know of, in contrast to breakings of the same algebra, remain 10-dimensional at any energy and reduce to...

view entire post

>Lorentz invariance at high energies, that is why we call it a deformation.

This is false. Any deformation of the Lorentz (or Poincare) algebra I know of, in contrast to breakings of the same algebra, remain 10-dimensional at any energy and reduce to...

view entire post

Finally your last message; well if you make basic errors, I tend to point them out, but I appreciate you like my succinct summary. Furthermore, there is no correct notion of locality in background independent approaches; there are however plenty of ansatze for what you would like locality to be. The problem is that none of these definitions are natural and resemble what an engineer does when has has to repair an ill constructed building.

Concerning your evaluation towards discrete approaches, I have worked on these issues for many years and actually most of the researchers I know share my opinion on this (at least in private).

Enjoy your chicken, I think the pepper sauce we just prepared will do fine.

Kind regards,

Johan

report post as inappropriate

Concerning your evaluation towards discrete approaches, I have worked on these issues for many years and actually most of the researchers I know share my opinion on this (at least in private).

Enjoy your chicken, I think the pepper sauce we just prepared will do fine.

Kind regards,

Johan

report post as inappropriate

>Finally your last message; well if you make basic errors, I tend to point them out, but I appreciate you like my succinct

>summary.

It was, as you know, a concern about your style of discussion, which I am happy to see you amended. Concerning the way science works, I am aware I have still to learn a lot, but I have read my Feyerabend and Lakatos, among others, and I do...

view entire post

>summary.

It was, as you know, a concern about your style of discussion, which I am happy to see you amended. Concerning the way science works, I am aware I have still to learn a lot, but I have read my Feyerabend and Lakatos, among others, and I do...

view entire post

Dear Daniele,

If your formalism allows you to consider finite open regions of space-time, then this is equivalent to inserting a classical boundary. Basically what you are probably doing is taking some fixed discrete structure, promoting this as a ''boundary'' and allow for fluctuations inside. Of course all these concepts depend at least on a background topology such as the notions of...

view entire post

If your formalism allows you to consider finite open regions of space-time, then this is equivalent to inserting a classical boundary. Basically what you are probably doing is taking some fixed discrete structure, promoting this as a ''boundary'' and allow for fluctuations inside. Of course all these concepts depend at least on a background topology such as the notions of...

view entire post

report post as inappropriate

Dear Daniele,

Concerning your second mail, did I ever dispute the fact that the q-deformed algebra's are not closed ? All I said is that they seriously differ from the Poincare algebra at high energies. Moreover, it is not enough to have the algebra only, you need to have the entire deformed group with it's complicated topology. The reason is very simple, the quantization of spin is a property of the orthochronous Lorentz group and not the algebra. And yes, I use terminology in a loose way because we have no space-time understanding whatsoever yet of these deformed algebraic structures; I invite you to construct its representation theory.

Concerning the development of this mathematical theory; yes, I am also glad people do it and I have played with these things myself once upon a time.

The development of representation theory of these deformed algebra's is still in its infancy which again does not imply it should stop, but on the other hand (and that was my point) my intuition tells me that even this kind of mathematical structures are not broad enough yet.

Concerning your statements about the motivation for the deformation, I agree with what you try to say intuitively (not physically though). Of course, all this flies straight in the face of naturalness and moreover, your deformations should be fully dynamical. Haven't seen that anywhere yet...

Best,

Johan

report post as inappropriate

Concerning your second mail, did I ever dispute the fact that the q-deformed algebra's are not closed ? All I said is that they seriously differ from the Poincare algebra at high energies. Moreover, it is not enough to have the algebra only, you need to have the entire deformed group with it's complicated topology. The reason is very simple, the quantization of spin is a property of the orthochronous Lorentz group and not the algebra. And yes, I use terminology in a loose way because we have no space-time understanding whatsoever yet of these deformed algebraic structures; I invite you to construct its representation theory.

Concerning the development of this mathematical theory; yes, I am also glad people do it and I have played with these things myself once upon a time.

The development of representation theory of these deformed algebra's is still in its infancy which again does not imply it should stop, but on the other hand (and that was my point) my intuition tells me that even this kind of mathematical structures are not broad enough yet.

Concerning your statements about the motivation for the deformation, I agree with what you try to say intuitively (not physically though). Of course, all this flies straight in the face of naturalness and moreover, your deformations should be fully dynamical. Haven't seen that anywhere yet...

Best,

Johan

report post as inappropriate

Finally, glad you read so many books, I never studied what philosophers of science had to say about scientific practice. Scientists themselves should find that out. As a general comment to what you say, I think that your ideas apply to most people; however they are terribly outdated what I am concerned. Ultimately, progress always comes from a new idea which of course is grounded in the failure of an older one. But what usually happens is that the later generations forget about the idea and only learn the math; this is very problematic and completely outdated. Often it is so that a masterpiece of ''engineering'' leads to new abstract insights which by themselves open a whole new world. Far too often, this new world is not studied and people stick to the engineering example. The best examples here are general relativity and quantum theory. If you do not understand what I say, I will use more words for it.

The basic problem in all attempts to formulate a principle of locality for quantum spacetime is that in the continuum, this is a topological fact which has nothing to do with the dynamics. In algebraic approaches to quantum space-time you can see very easily where the problem resides; in kappa Minkowski for example the space coordinates commute and do not commute with the time coordinate. So, first you have to define an event, are you going to say that it corresponds to eigenvectors in a representation which diagonalize the position coordinates, so that an event is effectively non-local in time? Clearly such thing is not invariant under the deformed group because time and space mix. So an event will become ''coordinate dependent'', likewise will the notion of neighborhood be. Actually, depending upon your deformation parameter, one single event in one coordinate system may stretch out formidably in another. So the laws themselves will have a non-locality scale depending upon this stretching. Of course, all such approaches seriously tamper with diffeomorphism invariance which is very poorly understood in that context (Majid once made an attempt). In my book, that reads like having an effective class of coordinate systems.

Best,

Johan

report post as inappropriate

The basic problem in all attempts to formulate a principle of locality for quantum spacetime is that in the continuum, this is a topological fact which has nothing to do with the dynamics. In algebraic approaches to quantum space-time you can see very easily where the problem resides; in kappa Minkowski for example the space coordinates commute and do not commute with the time coordinate. So, first you have to define an event, are you going to say that it corresponds to eigenvectors in a representation which diagonalize the position coordinates, so that an event is effectively non-local in time? Clearly such thing is not invariant under the deformed group because time and space mix. So an event will become ''coordinate dependent'', likewise will the notion of neighborhood be. Actually, depending upon your deformation parameter, one single event in one coordinate system may stretch out formidably in another. So the laws themselves will have a non-locality scale depending upon this stretching. Of course, all such approaches seriously tamper with diffeomorphism invariance which is very poorly understood in that context (Majid once made an attempt). In my book, that reads like having an effective class of coordinate systems.

Best,

Johan

report post as inappropriate

Dear Sir,

You say that whether reality is digital or analog “refers, at least implicitly, to the ‘ultimate’ nature of reality, the fundamental layer.” You admit that “I do not know what this could mean, nor I am at ease with thinking in these terms.” Then how could you discuss the issue scientifically? Science is not about beliefs or suppositions. Your entire essay exhibits your beliefs and suppositions that are far from scientific descriptions. You admit it when you talk about “speculative scenario”. This is one of the root causes of the malaise that is endemic in scientific circles. Thus, theoretical physics is stagnating for near about a century while experimental physics is achieving marvelous results.

Let us take the example of space. You have not defined reality since you admit you have no idea about it. You discuss space without defining it. Both space and time are related to the order of arrangement in the field, i.e., sequence of objects and events contained in them like the design on a fabric. Both space and time co-exist like the fabric and its back ground color. The perception of each sequence is interrupted by an interval however infinitesimal. The interval between objects is called space and that between events is called time. We take a fairly intelligible and repetitive interval and use it as the unit, where necessary by subdividing it. We compare the designated interval with this unit interval and call the result measurement of space and time respectively.

Since space and time have no physical existence like particles and fields, we use alternative symbolism of objects and events to describe them. Thus, what Euclid called space is not the interval between objects, but the basic frame of reference on which the objects are placed as markers. To this extent he is right. Dedekind and others did not know this concept. Hence they wrongly held that “it is possible to construct discontinuous spaces in which Euclidean geometry holds”. Geometry is related to measurement of space and no measurement except distance (line) is possible in discontinuous spaces like in the interval between a point on Earth and another point on the Sun or Moon. However, this fallacy was not apparent to the others who built theories upon such invalid foundation. Since space is the interval between objects, the space is continuous throughout the Universe. Thus your definition of quantum space is fundamentally wrong. Hence it is no wonder that you conclude “the question has no absolute meaning, so no answer.”

The rest of your essay also exhibits the same beliefs and suppositions. Thus, it is strange that it has been highly rated by the FQXi community. Possibly “novelty of presentation (which means talking admittedly vaguely)” and incomprehensibility are the Bench marks of scientific excellence these days.

Regrds,

basudeba.

report post as inappropriate

You say that whether reality is digital or analog “refers, at least implicitly, to the ‘ultimate’ nature of reality, the fundamental layer.” You admit that “I do not know what this could mean, nor I am at ease with thinking in these terms.” Then how could you discuss the issue scientifically? Science is not about beliefs or suppositions. Your entire essay exhibits your beliefs and suppositions that are far from scientific descriptions. You admit it when you talk about “speculative scenario”. This is one of the root causes of the malaise that is endemic in scientific circles. Thus, theoretical physics is stagnating for near about a century while experimental physics is achieving marvelous results.

Let us take the example of space. You have not defined reality since you admit you have no idea about it. You discuss space without defining it. Both space and time are related to the order of arrangement in the field, i.e., sequence of objects and events contained in them like the design on a fabric. Both space and time co-exist like the fabric and its back ground color. The perception of each sequence is interrupted by an interval however infinitesimal. The interval between objects is called space and that between events is called time. We take a fairly intelligible and repetitive interval and use it as the unit, where necessary by subdividing it. We compare the designated interval with this unit interval and call the result measurement of space and time respectively.

Since space and time have no physical existence like particles and fields, we use alternative symbolism of objects and events to describe them. Thus, what Euclid called space is not the interval between objects, but the basic frame of reference on which the objects are placed as markers. To this extent he is right. Dedekind and others did not know this concept. Hence they wrongly held that “it is possible to construct discontinuous spaces in which Euclidean geometry holds”. Geometry is related to measurement of space and no measurement except distance (line) is possible in discontinuous spaces like in the interval between a point on Earth and another point on the Sun or Moon. However, this fallacy was not apparent to the others who built theories upon such invalid foundation. Since space is the interval between objects, the space is continuous throughout the Universe. Thus your definition of quantum space is fundamentally wrong. Hence it is no wonder that you conclude “the question has no absolute meaning, so no answer.”

The rest of your essay also exhibits the same beliefs and suppositions. Thus, it is strange that it has been highly rated by the FQXi community. Possibly “novelty of presentation (which means talking admittedly vaguely)” and incomprehensibility are the Bench marks of scientific excellence these days.

Regrds,

basudeba.

report post as inappropriate

Daniele

I wish to warmly congratulate you on your provisional 1st place.

I hope now the 'competitive' pressure has gone we may return to good science. I'd be very appreciative if you read and genuinely commented on the model in my essay, which I beleive may be of major significance. http://fqxi.org/community/forum/topic/803

Very many thanks

Peter

report post as inappropriate

I wish to warmly congratulate you on your provisional 1st place.

I hope now the 'competitive' pressure has gone we may return to good science. I'd be very appreciative if you read and genuinely commented on the model in my essay, which I beleive may be of major significance. http://fqxi.org/community/forum/topic/803

Very many thanks

Peter

report post as inappropriate

Hi,

believe me, the only reason why I could not read or comment all the essays that I would have wanted had nothing to do with competitive pressure, but only with the fact that I tried to keep doing good science. As a consequence, I do not have as much time as I would want.

I'll try to read your essay, as you suggest, and let you know of comments, should I have any that could be of interest.

best,

Daniele

believe me, the only reason why I could not read or comment all the essays that I would have wanted had nothing to do with competitive pressure, but only with the fact that I tried to keep doing good science. As a consequence, I do not have as much time as I would want.

I'll try to read your essay, as you suggest, and let you know of comments, should I have any that could be of interest.

best,

Daniele

Dear Daniele Oriti,

Congratulations upon your placing first in the community voting.

Edwin Eugene Klingman

report post as inappropriate

Congratulations upon your placing first in the community voting.

Edwin Eugene Klingman

report post as inappropriate

Hi,

and congratulations on your placing second! I think that finer differences do not really mean much, at this stage, and all those essays that classified roughly at the top have really been appreciated equally. Anyway, good to have our work somehow valued positively, isn't it?

ciao

Daniele

and congratulations on your placing second! I think that finer differences do not really mean much, at this stage, and all those essays that classified roughly at the top have really been appreciated equally. Anyway, good to have our work somehow valued positively, isn't it?

ciao

Daniele

Dear Daniele,

I share Peter Jackson's view when he says "I wish to warmly congratulate you on your provisional 1st place. I hope now the 'competitive' pressure has gone we may return to good science." I also hope that the top essay authors are still willing to consider the pesky questions of the dedicated amateurs. I have one for you which have I started with Ian Durham just recently incidentally:

Q: Coulomb's Law of electrostatics was modelled by Maxwell by mechanical means after his mathematical deductions as an added verification, which I highly admire. To me, this gives his equation some substance. I have a problem with the laws of gravity though, especially the mathematical representation that "every object attracts every other object equally in all directions." The 'fabric' of spacetime model of gravity doesn't lend itself to explain the law of electrostatics. Coulomb's law denotes two types of matter, one 'charged' positive and the opposite type 'charged' negative. An Archimedes screw model for the graviton can explain -both- the gravity law and the electrostatic law, whilst the 'fabric' of spacetime can't. Doesn't this by definition make the helical screw model better than than anything else that has been suggested for the mechanism of the gravity force?? Otherwise the unification of all the forces is an impossiblity imo. Do you have an opinion on my analysis at all?

report post as inappropriate

I share Peter Jackson's view when he says "I wish to warmly congratulate you on your provisional 1st place. I hope now the 'competitive' pressure has gone we may return to good science." I also hope that the top essay authors are still willing to consider the pesky questions of the dedicated amateurs. I have one for you which have I started with Ian Durham just recently incidentally:

Q: Coulomb's Law of electrostatics was modelled by Maxwell by mechanical means after his mathematical deductions as an added verification, which I highly admire. To me, this gives his equation some substance. I have a problem with the laws of gravity though, especially the mathematical representation that "every object attracts every other object equally in all directions." The 'fabric' of spacetime model of gravity doesn't lend itself to explain the law of electrostatics. Coulomb's law denotes two types of matter, one 'charged' positive and the opposite type 'charged' negative. An Archimedes screw model for the graviton can explain -both- the gravity law and the electrostatic law, whilst the 'fabric' of spacetime can't. Doesn't this by definition make the helical screw model better than than anything else that has been suggested for the mechanism of the gravity force?? Otherwise the unification of all the forces is an impossiblity imo. Do you have an opinion on my analysis at all?

report post as inappropriate

Dear Alan,

thanks for your interest. As I replied to Peter, the reason why I did not reply and comment to all the submitted essays and contributed ideas is simply that, whatever their interest, I have not enough time to do so. I would like to, but I simply cannot. I do not know your model, and it will take some time to study and try to understand it. Therefore I cannot comment on it. As a general remark, I do of course agree that a theory that explains gravity at a more fundamental level, which is what models of quantum space or related quantum gravity models try to do, and that in addition explains electromagnetism (electrostatics is not enough) and possibly other interactions (i.e. nuclear ones) would be better than one that only explains gravity. Unfortunately, I do not know any such complete theory yet.

Best,

Daniele

thanks for your interest. As I replied to Peter, the reason why I did not reply and comment to all the submitted essays and contributed ideas is simply that, whatever their interest, I have not enough time to do so. I would like to, but I simply cannot. I do not know your model, and it will take some time to study and try to understand it. Therefore I cannot comment on it. As a general remark, I do of course agree that a theory that explains gravity at a more fundamental level, which is what models of quantum space or related quantum gravity models try to do, and that in addition explains electromagnetism (electrostatics is not enough) and possibly other interactions (i.e. nuclear ones) would be better than one that only explains gravity. Unfortunately, I do not know any such complete theory yet.

Best,

Daniele

Thanks Daniele,

I have plans to include the gravity force as well. You're all right, I need a working simualtion model that canb speak for itself.

Kind regards,

Alan

report post as inappropriate

I have plans to include the gravity force as well. You're all right, I need a working simualtion model that canb speak for itself.

Kind regards,

Alan

report post as inappropriate

Since Danielle Oriti declared having no time for replying to criticism, I will just add remarks:

He wrote: "The idea of a cosmological phase transition of space itself, replacing the Big Bang singularity, may provide a novel way to look at the puzzles of very early cosmology (horizon problem, flatness problem, etc), currently address by inflation, itself in need for a better explanation".

Such promise is of course welcome even without a tangible basis.

Danielle Oriti admitted in reply to Wilhelmus de Wilde: "Concerning singularities, indeed, several if not all practicing scientists believe the notion of singularity is but a label for a physical situation we do not understand yet, but not something physical in itself. However, the task is then to build up a theory of what happens in such situations, and unfortunately to simply deny their realities is not enough. We all have to be able to do better."

I do not just agree on that. My essay tries to show a way that does not need the coward and lazy "it depends". Instead it offers an admittedly highly unwelcome approach:

In order to do better let's focus on possible flaws in very basics of mathematics and its relationship to physics.

Admittedly I am guided by my experience as an engineer: I like using singularities - as tools -, not as something real. I am fully aware that there is no ideal line current and no ideal point charge.

Eckard Blumschein

report post as inappropriate

report post as inappropriate

He wrote: "The idea of a cosmological phase transition of space itself, replacing the Big Bang singularity, may provide a novel way to look at the puzzles of very early cosmology (horizon problem, flatness problem, etc), currently address by inflation, itself in need for a better explanation".

Such promise is of course welcome even without a tangible basis.

Danielle Oriti admitted in reply to Wilhelmus de Wilde: "Concerning singularities, indeed, several if not all practicing scientists believe the notion of singularity is but a label for a physical situation we do not understand yet, but not something physical in itself. However, the task is then to build up a theory of what happens in such situations, and unfortunately to simply deny their realities is not enough. We all have to be able to do better."

I do not just agree on that. My essay tries to show a way that does not need the coward and lazy "it depends". Instead it offers an admittedly highly unwelcome approach:

In order to do better let's focus on possible flaws in very basics of mathematics and its relationship to physics.

Admittedly I am guided by my experience as an engineer: I like using singularities - as tools -, not as something real. I am fully aware that there is no ideal line current and no ideal point charge.

Eckard Blumschein

report post as inappropriate

True, I do not have as much time as I would like to reply to all messages. Despite this, I did reply to quite a few of them, and tried both to clarify my point of view, and to counterargue some criticisms. But let me understand: what is, exactly, your ciriticism? I have tried to present a point of view according to which the answer: ''it depends'' has a clear meaning (beside the ironic tone), and it is a shorthand for ''it depends on the specific phase and regime of approximation in which quantum space is and is probed, just like in any condensed matter system, and we may have a formalism for studying all these phases and approximations, we just have to work much harder and do it properly''. So, I don't see what is cowardly and lazy about it. Beside, I don't see the use of using this type of tone and empty statements.

Daniele

Daniele

Dear Daniele,

You wrote: "... the notion of singularity is but a label for a physical situation we do not understand yet, but not something physical in itself."

Why did you not at least try to reveal the reason for this calamity? Maybe an answer can be found here:

''it depends on the specific phase and regime of approximation in which quantum space is and is probed, just like in any condensed matter system, and we may have a formalism for studying all these phases and approximations, we just have to work much harder and do it properly''

For you and many others, mathematics including quantum space and a lot of formalisms seem to be undoubtedly correct and absolutely adequate without any (foundational) question.

You might feel my essay provocative and bold.

I found three mathematical pillars of physics affected from unjustified generalization.

Please do not hesitate taking issue if I am wrong and you have enough time.

Regards,

Eckard

report post as inappropriate

You wrote: "... the notion of singularity is but a label for a physical situation we do not understand yet, but not something physical in itself."

Why did you not at least try to reveal the reason for this calamity? Maybe an answer can be found here:

''it depends on the specific phase and regime of approximation in which quantum space is and is probed, just like in any condensed matter system, and we may have a formalism for studying all these phases and approximations, we just have to work much harder and do it properly''

For you and many others, mathematics including quantum space and a lot of formalisms seem to be undoubtedly correct and absolutely adequate without any (foundational) question.

You might feel my essay provocative and bold.

I found three mathematical pillars of physics affected from unjustified generalization.

Please do not hesitate taking issue if I am wrong and you have enough time.

Regards,

Eckard

report post as inappropriate

Dear Sir,

Mr. Peter Jackson, one of the finalists had asked us some clarifications. We think it may be of interest to you. Hence we post the reply to him below your Essay.

First let us answer to your question regarding how direct observation could be different. Since you are fond of spectroscopy, we will give you an example from that branch. Look at the mechanism behind the emission...

view entire post

Mr. Peter Jackson, one of the finalists had asked us some clarifications. We think it may be of interest to you. Hence we post the reply to him below your Essay.

First let us answer to your question regarding how direct observation could be different. Since you are fond of spectroscopy, we will give you an example from that branch. Look at the mechanism behind the emission...

view entire post

report post as inappropriate

Caro Daniele

Your essay concentrates on quantized space - but should not the building blocks of space be the also the same as those making up matter?

In a recent post above you said "As a general remark, I do of course agree that a theory that explains gravity at a more fundamental level, which is what models of quantum space or related quantum gravity models try to do, and that in addition explains electromagnetism (electrostatics is not enough) and possibly other interactions (i.e. nuclear ones) would be better than one that only explains gravity. Unfortunately, I do not know any such complete theory yet."

I have presented just such a theory but it is incomplete say the least. Moreover for my model to function some basic notions of present-day physics (specifically GR, the notion of flexible space-time, the point photon, and of quantum probability) have to be reconstructed or reverse-engineered to a common and simpler theory - In my 2005 Beautiful Universe theory on which my present fqxi paper is based, a universal lattice of dielectric building blocks store angular momentum in units of h and transmit it to neighboring nodes. Gravitational potential (density) is caused by the rate of rotation of the nodes, and the pattern of twisting of the axes of rotation in the lattice. I would highly appreciate it if you can look at my ideas. They would only work if professionals like you pick them up and work out the details!

With best wishes for your success, Vladimir

report post as inappropriate

Your essay concentrates on quantized space - but should not the building blocks of space be the also the same as those making up matter?

In a recent post above you said "As a general remark, I do of course agree that a theory that explains gravity at a more fundamental level, which is what models of quantum space or related quantum gravity models try to do, and that in addition explains electromagnetism (electrostatics is not enough) and possibly other interactions (i.e. nuclear ones) would be better than one that only explains gravity. Unfortunately, I do not know any such complete theory yet."

I have presented just such a theory but it is incomplete say the least. Moreover for my model to function some basic notions of present-day physics (specifically GR, the notion of flexible space-time, the point photon, and of quantum probability) have to be reconstructed or reverse-engineered to a common and simpler theory - In my 2005 Beautiful Universe theory on which my present fqxi paper is based, a universal lattice of dielectric building blocks store angular momentum in units of h and transmit it to neighboring nodes. Gravitational potential (density) is caused by the rate of rotation of the nodes, and the pattern of twisting of the axes of rotation in the lattice. I would highly appreciate it if you can look at my ideas. They would only work if professionals like you pick them up and work out the details!

With best wishes for your success, Vladimir

report post as inappropriate

Hi dear Daniele,

I had not read your essay, now yes, It's full of interesting things. Congratulations,and good luck for the final.

Steve

report post as inappropriate

I had not read your essay, now yes, It's full of interesting things. Congratulations,and good luck for the final.

Steve

report post as inappropriate

Well, thanks a lot for reading it, and for your kind message. I am happy you liked it.

ciao

Daniele

ciao

Daniele

Dear Daniele

What is your prognoses about Fermilab experiment?

http://holometer.fnal.gov/

http://www.fnal.gov/dir

ectorate/program_planning/Nov2009PACPublic/holometer-proposa

l-2009.pdf

All the best

Yuri

report post as inappropriate

What is your prognoses about Fermilab experiment?

http://holometer.fnal.gov/

http://www.fnal.gov/dir

ectorate/program_planning/Nov2009PACPublic/holometer-proposa

l-2009.pdf

All the best

Yuri

report post as inappropriate

Hello Daniele,

I have another bugging question for you. I'm 100% convinced that this proposed 'inclination hypothesis' will be 100x more enlightening than the Archimedes screw model for the graviton/anti-graviton. It's a real eye-opener this one.

The precession of Mercury can be explained in the same way that the 100,000 year glacial cycle can be explained by the inclination hypothesis that has reduced tide raising forces with increased inclination. The reduced tides lowers the distribution of warm equatorial waters to the poles, which induces glaciation in the high latitudes. The combination of these two papers Spectrum of 100-kyr glacial cycle: Orbital inclination, not eccentricity and The 1,800-year oceanic tidal cycle: A possible cause of rapid climate change can be used to reconcile the 1,800 year cycle to the 1,470 year cycle seen in physical data Timing of Abrupt Climate Change: A Precise Clock.

I've scanned a quick doodle from last night which shows how the planet Mercury, due to it's high eccentricity, has very different distances above and below the orbital plane when nearing the planet and when furthest away. This means that the tide raising forces will be very different from one half of it's inclination orbit compared to the other half, despite it only having an inclination angle of around 6 degrees. This difference in gravitational forces from the calculated Newtonian forces is the reason for the discrepancy of it's orbital precession. I need to do the calcs, I know.

This proposed increase in gravitational attraction on the rotational plane of a celestial body has a surprising number of possible examples. This article on the Pan and Atlas moons of Saturn mentions the problem of their formation from ring debris alone, it simply wouldn't happen under the gravity laws. They say that a gravitational 'seed' would be needed which is exactly the same conclusion that the Harvard professors came to when analysing their 360 mile wide innermost core of the Earth Earth's New Center May Be The Seed Of Our Planet's Formation.

Kind regards,

Alan

attachments: 1_Doodle.jpg

report post as inappropriate

I have another bugging question for you. I'm 100% convinced that this proposed 'inclination hypothesis' will be 100x more enlightening than the Archimedes screw model for the graviton/anti-graviton. It's a real eye-opener this one.

The precession of Mercury can be explained in the same way that the 100,000 year glacial cycle can be explained by the inclination hypothesis that has reduced tide raising forces with increased inclination. The reduced tides lowers the distribution of warm equatorial waters to the poles, which induces glaciation in the high latitudes. The combination of these two papers Spectrum of 100-kyr glacial cycle: Orbital inclination, not eccentricity and The 1,800-year oceanic tidal cycle: A possible cause of rapid climate change can be used to reconcile the 1,800 year cycle to the 1,470 year cycle seen in physical data Timing of Abrupt Climate Change: A Precise Clock.

I've scanned a quick doodle from last night which shows how the planet Mercury, due to it's high eccentricity, has very different distances above and below the orbital plane when nearing the planet and when furthest away. This means that the tide raising forces will be very different from one half of it's inclination orbit compared to the other half, despite it only having an inclination angle of around 6 degrees. This difference in gravitational forces from the calculated Newtonian forces is the reason for the discrepancy of it's orbital precession. I need to do the calcs, I know.

This proposed increase in gravitational attraction on the rotational plane of a celestial body has a surprising number of possible examples. This article on the Pan and Atlas moons of Saturn mentions the problem of their formation from ring debris alone, it simply wouldn't happen under the gravity laws. They say that a gravitational 'seed' would be needed which is exactly the same conclusion that the Harvard professors came to when analysing their 360 mile wide innermost core of the Earth Earth's New Center May Be The Seed Of Our Planet's Formation.

Kind regards,

Alan

attachments: 1_Doodle.jpg

report post as inappropriate

Gentlemens

I wonder why you did not notice or do not want to notice the radical view that an independent investigator.Remember this name: name,Friedwardt Winterberg

http://bourabai.narod.ru/winter/relativ.htm

http://

bourabai.narod.ru/winter/clouds.htm

Yuri Danoyan

report post as inappropriate

I wonder why you did not notice or do not want to notice the radical view that an independent investigator.Remember this name: name,Friedwardt Winterberg

http://bourabai.narod.ru/winter/relativ.htm

http://

bourabai.narod.ru/winter/clouds.htm

Yuri Danoyan

report post as inappropriate

Hi Yuri,

Yes, Professor Wintergerg has got it to a tee. Spot on. Sorry for not looking sooner, although I find a direct link tends to aid a reader, such as The Einstein-Myth and the Crisis in Modern Physics (see link help page above).

I want to email him a.s.a.p and tell him about the Inclination Hypothesis. He'll love it, I'm sure.

Cheers Yuri,

Alan

report post as inappropriate

Yes, Professor Wintergerg has got it to a tee. Spot on. Sorry for not looking sooner, although I find a direct link tends to aid a reader, such as The Einstein-Myth and the Crisis in Modern Physics (see link help page above).

I want to email him a.s.a.p and tell him about the Inclination Hypothesis. He'll love it, I'm sure.

Cheers Yuri,

Alan

report post as inappropriate

I've taken the liberty of scanning Professor Taylor's new book where he talks about the current concensus opinion on the cause of the 100,000 year ice age cycle. It's a brillint summary of the situation as it stands. See attached and also attached to the next post.

Alan

attachments: 1_Dance_Of_Air__Sea1.jpg, 1_Dance_Of_Air__Sea2.jpg

report post as inappropriate

Alan

attachments: 1_Dance_Of_Air__Sea1.jpg, 1_Dance_Of_Air__Sea2.jpg

report post as inappropriate

Here's the next two pages..

attachments: 1_Dance_Of_Air__Sea3.jpg, 1_Dance_Of_Air__Sea.jpg

report post as inappropriate

attachments: 1_Dance_Of_Air__Sea3.jpg, 1_Dance_Of_Air__Sea.jpg

report post as inappropriate

Login or create account to post reply or comment.