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Ian Durham: on 5/23/20 at 21:58pm UTC, wrote Hi Luca, Hmm. I guess I must not be understanding the concept yet. I mean,...

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Luca Valeri: on 5/17/20 at 13:39pm UTC, wrote Dear Pavel and Dimitry, Thanks a lot for your rating, your kind reply and...

Pavel Poluian: on 5/15/20 at 7:33am UTC, wrote Dear Luca Valeri Zimmermann! We highly appreciate your serious work in the...

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FQXi FORUM
October 20, 2020

CATEGORY: Undecidability, Uncomputability, and Unpredictability Essay Contest (2019-2020) [back]
TOPIC: Semantically Closed Theories and the Unpredictable Evolution of the Laws of Physics by Luca Valeri [refresh]
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Author Luca Valeri wrote on Apr. 25, 2020 @ 17:45 GMT
Essay Abstract

In this essay I take symmetries as the conceptual basis that governs the structure of the laws the objects. It also defines under which condition a system can be viewed as separated from its environment. Only if a system can be separated from its environment the laws and concepts of a system are well defined. In my opinion this might lead to a new solution to the measurement problem in quantum mechanics. The separability condition of protects Wigner's friend measurement because Wigner's intervention destroys the symmetry and unitarity of Wigner's friend measurement and hence his measurement is not well defined any more. Objects, laws and environment build a unity which I call semantically closed theory. Taking into account the environment and the conditions under which quantities can be defined makes it thinkable that under different environmental conditions different symmetries and laws might emerge and be realized. I apply these ideas first to social sciences and philosophy of science. Then I apply this view to the arrow of time, where I show that the epistemic arrow of time might be explained by the succession of semantically closed theories, where the later contains the earlier. Finally the possibility of having physically systems with changing laws and concepts might correspond to changes of the axioms defining a physical system. This gives us a new perspective on how to think about consciousness in the context of Gödel's incompleteness theorem.

Author Bio

Masters in physics. Interested since ever in fundational questions of physics. Recently read Poincaré's Science and Hypothesis, which inspired a lot of what is written in this essay.

Download Essay PDF File

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Malcolm Riddoch wrote on Apr. 27, 2020 @ 09:16 GMT
Hi Luca,

an interesting application of Tarski’s notion of semantically closed languages on QM’s formalism! With regards to Wigner’s Friend:

“If an outside observer wants to make a measurement on a closed system, which is not compatible with the relative measurable quantities within that system, then the dynamics within that system is not unitary and not invariant under the symmetry any more” (p.4).

I’d only ask from whose perspective are we making these determinations? Is it the case that from the Friend’s perspective it is Wigner who is in a closed system with respect to the Friend’s lab and vice versa? Does the asymmetry then cut both ways in which case the application of QM laws is semantically closed both for Wigner’s perspective and his Friend’s?

To me this sounds like it leans towards a relational or relative-state interpretation. What do you think?

Also it looks like the scoring functionality is still down here so I'll have to wait to give you a rating.

Cheers,

Malcolm

Je suis, nous sommes Wigner!

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Author Luca Valeri replied on Apr. 27, 2020 @ 11:39 GMT
Hi Malcolm

Thanks for your reply. I do not know Tarski well. It would have been certainly very interesting to discuss Tarski in context of the essay contest question.

In a way, yes, the relational point of view. But this point of view can be made objective by shielding the system under consideration from outside intervention leading to contradicting propositions about what is. Separability from the rest of the world is condition under which the formulation of laws and definition of concepts is possible (very in Kantian way). This I would say is also true in classical physics. The need for such conditions however is not so urgent in classical physics.

Wigner has a owning the pure state has in a way a more objective view. While Wigner's friend has only a mixed state being an entangled subsystem of the whole. In that sense Wigner's view is more objective. But things get really complicated, when, as in your essay there are two Wigner which are on equal footing.

Luca

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Malcolm Riddoch replied on Apr. 28, 2020 @ 02:12 GMT
“In a way, yes, the relational point of view…Separability from the rest of the world is condition under which the formulation of laws and definition of concepts is possible.”

So your own personal ontology is, very generally speaking, a ‘relational objective realism’? And you claim that we can save the objectivity of a relational interpretation of QM by physically closing the...

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Michael Dascal wrote on Apr. 30, 2020 @ 01:03 GMT
Hi Luca,

Thanks for an interesting paper!

As I mentioend in my reply to you, as I see a number of similarities between some of what you say here and what I've said elsewhere. One thing that I'm a little confused by, though, has to do with what you say regarding separability of a quantum system and its enviroment. You write that your "interpretation protects the subjective view from contradictions by not allowing unwarranted outside interventions. It makes the subjective loss of the phase information objective and thus avoiding contradictions. Contrary to decoherence I ask the system to be separated from its environment in order for a measurement being well defined."

Do you mean to imply that when a system isn't isolated from its environment that it can't be said to have been 'measured'? If this is the case, then do you think there are different types of physical interactions in the world, some of which are measurements and some of which aren't?

Best,

Mike

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Author Luca Valeri replied on Apr. 30, 2020 @ 14:06 GMT
Hi Michael,

thanks for your question. I am very glad to answer, since this is a main point in my essay and maybe I was not explicit enough here. Especially because the view I want to push forward is very unorthodox.

First of all: there is only one kind of interaction. The distinguishing feature is in the kind of object or system, that is interacting with the primary object, which...

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Syed Raiyan Nuri Reza wrote on May. 2, 2020 @ 15:37 GMT
Dear Luca Valeri,

From what I understood ( and there is a decent amount of technicality that eluded me), I found your proposition of symmetries, objects, and laws only taken together are unitary and well defined a nuanced and rich concept.

It is truly an interesting way of addressing the measurement problem ( in so far as a layman and serious enthusiast understands) and an interesting avenue for Incompleteness Theorem(s) to enter the picture!

Best Wishes,

Raiyan Reza

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Author Luca Valeri replied on May. 2, 2020 @ 20:23 GMT
Dear Raiyan Reza,

Thanks for commenting on my essay and for the good rating. My first draft of my essay had much more technical details on representation theory of groups, on Poulin's relational measurement and on Wigner's friend. It had to go because of the 25 tsd character limmit and I wanted to keep the elaborations of the less usual consequences of this view. The technical stuff is part of the canon that one learns in quantum mechanics and when you read some stuff on the measurement problem.

However I will continue to work on the prove, that unitarity and symmetry is destroyed on the subsystem, if from outside a non compatible observable is measured (done by Wigner). To maintain unitarity and symmetry is crucial for doing an experiment or observation because very observation is indirect and one relies on the validity of the laws within the system to interpret the observation.

Thanks again

Luca

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Syed Raiyan Nuri Reza replied on May. 3, 2020 @ 20:55 GMT
Dear Luca Valeri,

You are most welcome!

It was a pleasure reading your ideas.

I intend to try to take QM or Physics related classes but that depends on my credit space ( Education background: A CS major here, switched from Physics due to financial obligations).

If not, I will try to self learn as much as possible! I had saved a copy of your essay and hope to re-read it when I posses a more in depth knowledge of QM and related topic.

All the best with your research, work and this contest!

Best Wishes,

Raiyan Reza

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Cristinel Stoica wrote on May. 4, 2020 @ 08:07 GMT
Dear Luca,

Very enjoyeable essay! I liked how you explained difficult concepts like the classification of the wavefunctions by spin and mass in terms of representations of the Poincaré symmetry, made by Wigner and Bargmann, the role (or absence of such a role) of the observer in various interpretations, decoherence, the measurement problem etc. I like this statement "the objects...

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Member Tejinder Pal Singh wrote on May. 4, 2020 @ 15:28 GMT
Dear Luca,

After reading your thoughtful essay I am wondering:

Can you take the actual development of physical theories since the time of Galileo and Newton, and arrange them the way you prescribe...[poorer to richer] and `predict' what should come next? At least in outline? i.e. is your construct predictable / unpredictable?

I am not sure if computability can also be addressed in this framework? Are richer theories better at computing?

I appreciate your original line of thinking. All the best,

Tejinder

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Author Luca Valeri replied on May. 4, 2020 @ 18:05 GMT
Dear Tejinder,

Thanks for your interest and for your important questions, that allows me to clarify some points in my essay.

The order from Newton to Einstein's theories of relativity is certainly something Heisenberg had in mind: older theories can be explained from newer ones but not vice versa. So I cannot from a relativistic standpoint predict what will come. For me this was just to illustrate, how there can be conceptual and structural dependencies between theories.

But my intent however is much more radical. I see the objective world as a realization of such mathematical structures. Where all quantities within the theory and the physical system are determined by specific measurements within the system. Not that 3 hundreds years ago Newtonian mechanics was realized and today relativity.

However the richer/later structure is not unpredictable from the earlier, because the initial conditions are not known exactly or the system is to complicated. But because we lack of word, concepts, structure of the later in the future realized structure. I belief this is true also for evolution and history of mankind. And maybe for free will and consciousness.

Computability has not been directly addressed. It has been criticized in the universal homo economicus example as tautological concepts with not much content, if not enriched with a concrete structure and meaning.

Luca

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Yutaka Shikano wrote on May. 4, 2020 @ 21:11 GMT
Dear Luca,

I learned a lot of things from prosaic style of your essay. You mentioned

Since in physics we are not used to imagine the laws and basic concept as something that could change, I shall briefly give two examples from totally different areas, where the changing of the laws is much easier to imagine.

"in physics we are not used to imagine" is this true in history of science? Around 16 centuries before Newton, the theory in physics, the imagination is important to create the laws of physics. Also, our building-up process of laws of physics, we often use the gendanken experiment such as quantum eraser. Is this different from the imagination?

Best wishes,

Yutaka

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Author Luca Valeri replied on May. 5, 2020 @ 16:20 GMT
Hi Yutaka

Thanks for reading my essay. In history of science often the new theory introduces concepts, that did not exist before and insofar is beyond the language and hence imagination(?) of the old theory.

Can you imagine what happens in a quantum eraser experiment? Strangely enough we get used to the strange (copenhagen) quantum reasoning and know, what will happen in these eraser experiment. But we cannot imagine what really happens. We understand without being able to imagine.

To extent our imagination was a bit the goal of this essay.

Luca

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Yutaka Shikano replied on May. 11, 2020 @ 00:52 GMT
Hi Luca,

On the quantum eraser experiment, this is too strange for the general public. On the other hand, such gendanken experiments seem to "real" in the researchers mind. From this thoughts, the real experiments should be "confirmed" or "verified" in some sense. This shows that the boundary between the realistic understanding and the imagination is wobbly or depends on the background understanding. From the historical viewpoint on scientific development, I hope that our understandings are improved.

Best wishes,

Yutaka

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Mozibur Rahman Ullah wrote on May. 5, 2020 @ 18:44 GMT
Dear Luca,

A really clear and interesting essay despite the many ideas that it references. It's a pleasure to read it.

I'm not sure that Poincare was right to say that Newtons first law is merely a definition. Personally speaking, I think that good definitions can be hard to come by, it's not always easy.

I like 'parts have meaning only in the context of the...

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Author Luca Valeri replied on May. 6, 2020 @ 05:29 GMT
Dear Mozibur Ullah,

Thanks for your nice interested comment. I'm glad my essay remained readable, despite a lot of ideas could only be referenced. The 25k character limit ... Each section could have become an essay in its own. But I wanted to connect these things. Wanted to tell the whole story.

You say: "I'm not sure that Poincare was right to say that Newtons first law is merely a definition. Personally speaking, I think that good definitions can be hard to come by, it's not always easy." Well Poincaré did not say 'merely'. But I was thinking the same: why, if it's merely a convention, is it so damn good to build up the theory? He only says it must be empirically guided. I found two answers: the first law defines the 'normal' behaviour of things. What it makes a good definition is that there exists a lot of things, that behave like that.

But finally Poincaré's hierarchical reconstruction of the laws is maybe a bit artificial. It builds up a web of meaningful connections. What is definition and what is empirical consequence becomes a bit blurry and is finally underdetermined.

Luca

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Michael muteru wrote on May. 6, 2020 @ 09:34 GMT
Dear Valeri. I learnt quite a lot from your essay.i was particularly interested in treating observer as object who participates in the universe.rated You accordingly. can cognitive Bias be a source of the science we partake?please take your time to read my take here .https://fqxi.org/community/forum/topic/3525.Thanks.Wish you all the best in the contest.

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Author Luca Valeri replied on May. 6, 2020 @ 09:54 GMT
Hi Michael,

thanks for your reply. Made me curious for your essay.

Luca

PS: by the way. Your rating seemed to have lowered my average rating. Which is fine. I appreciate the comment.

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Jochen Szangolies wrote on May. 7, 2020 @ 15:45 GMT
Dear Luca,

your essay touches on many interesting notions, and sketches some intriguing arguments. Indeed, it's so rich that I unfortunately found myself a bit lost, in places, and could not always follow the thread of argumentation you present. Perhaps it's owed to the contest's length constraints---which lord knows I've had my own struggles with---but I felt perhaps you might've chosen to...

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Author Luca Valeri wrote on May. 7, 2020 @ 22:37 GMT
Hi Jochen,

thanks very much for reading my essay and for your reply. You are right. My essay is really fully packed and there was a lot, that I had to led go. The goal was to justify a view, where all concepts emerge from there relations to there surrounding, even the objects and their properties. This means in different configurations different objects and laws emerge, which might or might not be compatible with each other. This is difficult to imagine as we usually imagine fixed objects with fixed properties moving according the laws.

Von Weizsäcker plays a huge role in my thinking. In fact the name semantically closed theories is a mixture of Heisenberg's closed theories and Von Weizsäcker's semantically consistent theories in his philosophy of 'Kreisgang'. In his book Time and Knowledge he tries to develop a temporal logic. At the very beginning he describes the meaning of propositions as imagination of possible actions. So that the meaning of concepts corresponds to physical operations which depend on the laws. In my opinion, this might bridge the gap - as you say - between the formalized languages and the physical world. That is why I immediately start with relation between objects. And try to find meaning in this relations.

Tarsky I learned to know a little only recently, while I was writing. Sounds really interesting.

Luca

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Israel Perez wrote on May. 8, 2020 @ 03:32 GMT
Dear Luca

Nice and well discussed essay. You touch several important topics which are related to symmetries. I guess my favorite one is the arrow of time. It is indeed an exciting topic that I have studied a bit. There is a nice book authored by H Zeh who deals with this perplexing problem. Are you aware of this book? I am still struggling with the concept of time. As far as we understand, time is quite linked with motion for the rate of flow of time depends on speed and gravity. You mention that we do not have memories of the future. Indeed, we only remember events that are taking place (present), not events that have not taken place (the future). Then we stored these present events that turn into past memories as they are replaced in sequence by new ones. In this sense I agree that we remember the past, but in my view, we are just remembering present events. The fact that most physical laws are symmetric with respect to time reversal, implies that there is a problem in the way we are expressing those laws. For as you mention, the law of entropy seems to define a direction of time. What are your thoughts on these matter?

Best regards

Israel

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Author Luca Valeri replied on May. 8, 2020 @ 19:01 GMT
Dear Israel,

Thanks for your kind reply. Symmetry is so central in the conceptualisation of physics and in my opinion part of the conditions of the possibility to make science at all. And yet rarely it is used a foundational principle for the derivation of the structure of physics - beyond the practicality.

And the symmetry or asymmetry of time is the most difficult one. If time would not 'appear' asymmetric, there would be no need to do any physics. And yet it is difficult not to see explain the asymmetry as an epistemic notion of our course grained perception.

Sometime I think the problem time is the reverse one than the usually discussed. And the question is: How can one derive the time symmetric laws from the asymmetric phenomena and operationalization of actions.

Thanks for pointing me out Zeh's book.

Luca

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Israel Perez replied on May. 9, 2020 @ 19:09 GMT
Dear Luca

Thanks for your reply. That is the difficult part. Zeh's book is entitled "The arrow of time", I am sure you will like it.

Good luck in the contest!

Regards

Israel

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Satyavarapu Naga Parameswara Gupta wrote on May. 8, 2020 @ 08:22 GMT
Dear Dr Luca,

Thank you for writing a wonderful essay. Some of your nice words are ...........Wigner wrote that one of Newtons big accomplishments that made modern science possible is "the distinction between initial conditions and laws of nature."[14] Whereas the initial conditions might be complicated the laws are not..........

Thank you for your well studied wisdom words!

I want to say that Dynamic Universe model developed by me 40 years back under the guidance given by Maa Vak is also a direct application of Newtonian Physics. This model solved many unsolved problems and many of its predictions came true. This model is a general N-body problem solution.

You are inspired by by Poincaré's math and hypothesis, so do I !!! Poincaré's work is on general N-body problem solution, I think you know that.

Many similarities !!!

I hope you will find some time to look at my essay at " https://fqxi.org/community/forum/topic/3416 "

Best Regards

=snp

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John Joseph Vastola wrote on May. 12, 2020 @ 15:32 GMT
You discuss quite a lot of topics in your essay! One thing I wonder, based on what you wrote: how can we know when we have a semantically closed theory?

John

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Satyavarapu Naga Parameswara Gupta replied on May. 12, 2020 @ 18:58 GMT
Dear Dr Luca,

This is one more similarity with Dynamic Universe model.

It was proved by Dynamic Universe model by simulations, all the matter and radiation that are ejected out, from the Galaxy at the edge of Universe will be attracted by Universre and comeback into the Universe.... Have a look at my Blog.............

" https://vaksdynamicuniversemodel.blogspot.com/...

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Author Luca Valeri replied on May. 13, 2020 @ 14:29 GMT
Hi John,

Very good question! Thanks for asking it. By definition every quantity has do be defined and must be measurable within the theory. I would say as a first instance this can be decided formally within the theory. In the reconstruction in the essay you have a symmetry defining the basic quantities. Also the free evolution is defined. Then one needs an interaction, that correlates...

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Satyavarapu Naga Parameswara Gupta replied on May. 13, 2020 @ 21:33 GMT
Dear Dr Luca,

Very good explanatory answer with wonderful knowledge. You touched Newtonian Gravity, MOND, GTR etc in cosmology in addition to quantum field theories. I was working on this Dynamic Universe Model using Newtonian Gravitation and got many results.

I was feeling sorry to say that you did not yet looked at my essay. I hope you will get some time before closure of this contest....

Give me your mail ID so that we can discuss even after this contest

Best wishes to your essay

=snp

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Anonymous wrote on May. 14, 2020 @ 11:04 GMT
Hi Luca,

In response to your comment on my essay.... I believe there is a single Arrow-of-Time: the radiation AoT (see my ref's. on ECD). The asymmetry between past and future in terms of memory stems from logical consistency:

"...and indeed, the ‘memory’ of our future is much more selective than that of our past. Had we ‘remembered’ also everything from our future, we would surely choose, whenever possible, to avoid its unpleasant aspects, thereby creating a paradox."

As you note, a future memory of a truly original `thing' is initially necessarily "fuzzy", as that thing is not yet present in one's normal experience (to be contrasted with `future memories' of simple variations of existing things, which need not be fuzzy).

I have thought a lot about the possibility of factoring-in our own limitations, as observers, into our description of `reality'. I once even thought that, since we are essentially some `representation' of the laws of physics, there is no real mystery as to why we can describe nature so effectively with our invented theories. But as with Goedel's theorem, you need an `outside look' at a physicist which, being a physicist, you are not privileged to. Ultimately, only a solipsistic stance is consistent, which takes you outside the scope of physics (or anything communicable for that matter).

I enjoyed reading your essay,

Yehonatan

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Pavel Vadimovich Poluian wrote on May. 15, 2020 @ 07:33 GMT
Dear Luca Valeri Zimmermann!

We highly appreciate your serious work in the highest sense. We are happy to inform you that our rating of your essay is 10 points. Only one important issue needs clarification... Henri Poincare wrote of "hidden axioms". For example, we take a complete turn as something given. But you can imagine a world where the rotation around its own axis will never end! Can we extend your approach to worlds with other fundamental foundations?

We wish you a successful scientific work!

Truly yours,

Pavel Poluian and Dmitry Lichargin,

Siberian Federal University.

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Author Luca Valeri replied on May. 17, 2020 @ 13:39 GMT
Dear Pavel and Dimitry,

Thanks a lot for your rating, your kind reply and the question.

I am not sure about Poincaré's hidden axioms. I have read about the hidden definitions. Although axiom and definition might be the same. But to return to your question: Yes, I think - and that was exactly the point of my essay - that it is possible to apply it to different foundations. In my approach it is the symmetry group defining the foundation - the basic concepts. One can imagine, that under different environmental conditions different symmetries are realized. For instance in free space or near black holes. Leading to different fundamental laws and objects.

The main difficulty is then on how to describe the change from one system to the other as objects do not maintain their identity and the fundamental laws and concepts change. I don't know, how one could do that.

I imagine the following situation: In free space objects and system are well defined. (The free space or vacuum itself is not defined independently of the laws or symmetries. It is itself as the objects of the theory an emergent thing.) If there is an external force like gravity, the identity of the objects and the free laws can be maintained and the force is treated as an external disturbance. This is a good and well defined approximation as long the back reaction of the system is small enough. But when gravitational forces are becoming to big, the approximation do not hold any more. We have to look for new symmetries, which create or define new separable objects and systems. These determine new foundational concepts and new laws.

Luca

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Member Ian Durham wrote on May. 19, 2020 @ 01:42 GMT
Hi Luca, this is a very interesting essay. I'll have to give this some thought. But I'm not entirely convinced by some of your examples. I like the way you've framed the argument in terms of semantically closed theories, but I'm not entirely sure such a theory even exists (but perhaps that it your point).

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Author Luca Valeri replied on May. 19, 2020 @ 13:44 GMT
Hi Ian,

Thanks for your reply. The question you raise is very interesting. In short I would say, that the standard model is semantically closed and General Relativity is not. GR needs the laws of optics for the definition of the Geodesic, or QM (atomic spectra) for a length scale. There are indications, that general covariant theories are not semantically closable.

On a mesoscopic,...

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Member Ian Durham replied on May. 20, 2020 @ 01:07 GMT
Hi Luca,

Very interesting. So the Standard Model is semantically closed? I guess I'm still not clear on what that means, then, because it seems to me that the Standard Model is built on quantum field theory which, in turn, is built on QM and SR. One could theoretically assume, I suppose, that SR is part of QFT and then take QFT (vis-a-vis the Standard Model) to be semantically closed, but that would seem to require that SR is itself semantically closed which doesn't make sense to me. So maybe I am missing the point entirely?

Ian

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Author Luca Valeri replied on May. 20, 2020 @ 05:13 GMT
Hi Ian,

why should SR not be closed or closable? SR basically means, that you have the Poincaré group as symmetry group. The irreducible representation define what a free particle is - given by the Casimir operators of the group: mass and spin. Then by gauche principles the interaction is derived. In QFT you have even, that particles are only defined as free particles, because the interaction changes the vacuum (which also depends on the particle definition) and would lead to different inequivalent representations in fock space ...

So the Poincaré group defines, when a system is free and separable from the environment etc. It defines the observables (except maybe for time, which is really difficult!).

The difficulty in general relativity is, that you do not have a global invariant symmetry group and cannot define invariant separable objects. That might be the cause, why it is not renormalizeable.

Luca

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