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ttch: on 11/10/12 at 22:40pm UTC, wrote Prof. Wharton: You write that the universe began in a special state of...

Eckard Blumschein: on 11/10/12 at 8:55am UTC, wrote Ken, Having put your point of view in question I am still hoping for your...

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FQXi FORUM
September 20, 2014

CATEGORY: FQXi Essay Contest - Spring, 2012 [back]
TOPIC: The Universe Is Not a Computer by Ken Wharton [refresh]
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Author Ken Wharton wrote on Aug. 24, 2012 @ 12:08 GMT
Essay Abstract

When we want to predict the future, we compute it from what we know about the present. Specifically, we take a mathematical representation of observed reality, plug it into some dynamical equations, and then map the time-evolved result back to real world predictions. But while this computational process can tell us what we want to know, we have taken this procedure too literally, implicitly assuming that the universe must compute itself in the same manner. Physical theories that do not follow this computational framework are deemed illogical, right from the start. But this anthropocentric assumption has steered our physical models into an impossible corner, primarily because of quantum phenomena. Meanwhile, we have not been exploring other models in which the universe is not so limited. In fact, some of these alternate models already have a well-established importance, but are thought to be mathematical tricks without physical signficance. This essay argues that only by dropping our assumption that the universe is a computer can we fully develop such models, explain quantum phenomena, and understand the workings of our universe.

Author Bio

Ken Wharton is a full professor in the Department of Physics and Astronomy at San Jose State University, and a member of FQXi. His research in the field of Quantum Foundations is focused on realistic models that reside in ordinary spacetime, especially those that feature the same time-symmetry as the phenomena they attempt to explain.

Download Essay PDF File




nmann wrote on Aug. 24, 2012 @ 17:25 GMT
Fine essay. As soon as I saw the title my mouth began watering. The Lagrangian Schema's entirely novel for me but fascinating.

I've been beating this drum regularly of late and as a result risk coming on like a crank. But when you have a fundamental physical process (strong fermionic interaction) that's officially NP-hard and specifically biological processes (cf. protein folding) that may well turn out to be, you have to wonder about the universality of computation, and even whether computational complexity itself might not be a fancy excuse for the fact that there's simply stuff that cannot be computed, full-stop.

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Author Ken Wharton replied on Aug. 28, 2012 @ 17:41 GMT
Thanks, glad it caught your interest. I suspect we're talking about two very different things, however. Perhaps you're concerned with objects that in principle follow some well-defined dynamical equations, but those equations just happen to be too complex to calculate to the required precision. I'm concerned with global rules that apply on the level of the Lagrangian density and the action, but have no corresponding Newtonian-style equations that always can describe time-evolution from a given state.

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nmann replied on Aug. 28, 2012 @ 17:57 GMT
I'm largely following David Tong and Jan Zaanen in reference to the fermion sign problem. "[T]oo complex to calculate with the required precision" doesn't even begin to describe what Zaanen calls "the nightmare of modern physics." There's no known mathematics capable of dealing with it and if Matthias Troyer and Uwe-Jens Wiese are right there probably won't be.

But thanks very much for the response.

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Author Ken Wharton replied on Aug. 28, 2012 @ 19:46 GMT
Ah, in that case there might be more overlap than I thought. I'll do some reading and let you know if I find any connections.

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nmann wrote on Aug. 24, 2012 @ 17:30 GMT
Probably should have said "might be a fancy excuse". Informal usage creeping in there.

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Michael Lee wrote on Aug. 24, 2012 @ 18:21 GMT
Dear Ken,

i enjoyed your well written essay and the new perspectives you gave me with it.

Michael Lee

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Author Ken Wharton replied on Aug. 28, 2012 @ 17:56 GMT
Thanks, Michael -- that was the hope!

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Peter Jackson wrote on Aug. 24, 2012 @ 19:53 GMT
Ken

Congratulations on beautifully arguing possibly the most important case ever for the future of physics. You'll find in my essay that I have actually commenced an ontological construction with mechanisms and logic based unknowingly on the principles you identify.

A wonderful debag of the anthropocentric view which gelled with my own views was Henrich J. Heine S. Norenzaya A doi:10.1038/466029a and I found we've still used anthropecentricity in CMBR anisotropy analysis and the lack of a consistent theory for the celestial plane (see my ref USNO Circ 179), which I have resolved, but in a way not familiar to Newtonian Humankind with current interpretations of relativity theory and QM.

The one issue I do have with your text is that one small word; 'one' is missing, in; "...there is no (ONE) preferred frame of reference." My reasons should become clear, related to the kinetic hierarchical 'nesting' of the Discrete Field Model. (You may recall we found commonality last year).

I've established real physical spacetime boundaries, and the quantum mechanism at work there implementing the relativistic effects observed.

The reason current mathematics do not map back to reality is identified and analysed. I thus revert to logic; the structure of Truth Propositional Logic' with an application to dynamic (Modal) logic (PDL) overcoming limitations of Cartesian systems in (geometric) vector space, to where the invalidity of motion in geometry extends. I suggest we need better maths and a new way of thinking in visualising evolutions of interactions of non zero spatial particles over non zero time.

Of course your analysis and rationale, as well as it's acceptability. go way beyond my own faltering explorations and I hope you may have produced the winning essay. The concept desperately needs exposure to the mainstream community.

Very well done. And I greatly look forward to your comments on mine.

Peter

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Author Ken Wharton replied on Aug. 28, 2012 @ 19:40 GMT
Hi Peter,

I'm afraid that I still can't find the commonality between our ideas, but thanks for your nice words, and best of luck in the contest.

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Peter Jackson replied on Aug. 31, 2012 @ 18:31 GMT
Ken.

To simplify; I found mapping abstraction back to reality does not describe nature using present mathematics. Substituting the strict disciplines of logic however allowed a model which appears to give far more consistent results.

The model challenges a few assumptions which I identify. I assume you haven't yet read the essay? It's quite dense but mainly conceptual. Too many and too little time I know. (I'm mainly in astronomy and quantum optics so speak different languages anyway).

Your rationalisation of the theoretical background to my work is none the less very helpful and encouraging. I hope to cite your work.

I do hope you can read mine and comment, and forgive the Shakespearian metaphors to help kinetic visualisation!

Best wishes

Peter

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Author Ken Wharton replied on Sep. 4, 2012 @ 19:59 GMT
Hi Peter,

Sounds like you're going farther than I am, if you're discarding *all* present mathematics as a possible template for reality. I'm just targeting one particular style of mathematics (the Newtonian Schema), but I rather like the basic framework of the Lagrangian approach.

I guess I just don't see how one can even *do* physics without any mathematics at all...

Your essay is tough going to try to extract your main points, and I'm afraid I'm not having much success.

Best, Ken

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Member Benjamin F. Dribus wrote on Aug. 24, 2012 @ 20:43 GMT
Dear Ken,

Thank you for the wonderful read. A few questions come to mind; please pardon their length.

1. It makes perfect sense to regard initial and final conditions as logical input in the classical setting and to thus obtain a unique solution by means of stationary action, but I am not clear on how you avoid a large configuration space in the quantum setting. If you take...

view entire post


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Author Ken Wharton replied on Aug. 28, 2012 @ 19:43 GMT
Dear Ben,

Thank you very much for the thoughtful questions. You're asking a lot of the same questions that I am, as I pursue this research program. Here are some attempts at answers, based on my current thinking. (Numbers match to your questions.)

1) The key question is why the path integral works in the first place. If you have to sum first, and then square, then you're correct:...

view entire post


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Member Benjamin F. Dribus replied on Sep. 3, 2012 @ 06:47 GMT
Ken,

Thanks for the detailed response. You have provided me with several pieces of information I didn't know, and several other ideas I will have to carefully consider. I share your preference for GR and its few simple principles. However, coming from a math background and working mostly with very nice things like algebraic schemes and complex manifolds, it is hard for me to believe that the physical world is based on similarly nice things. I expect successful theories beyond GR and the SM to still be based on simple principles, but possibly involving arbitrarily messy mathematics. Take care,

Ben

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Author Ken Wharton replied on Sep. 4, 2012 @ 20:00 GMT
Hi Ben,

Glad you found something useful here. And we're on the same page when it comes to the simple principles / messy mathematics – with GR being an excellent example.

Best, Ken

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Edwin Eugene Klingman wrote on Aug. 24, 2012 @ 22:31 GMT
Dear Ken Wharton,

It's great to see you back. Your current essay is one of the most enjoyable of this contest, and your perspective on this major issue is well thought out. Like many of us, you continue to evolve your previous essays into implied consequences.

I will come back with a longer comment, but a houseful of family and guests calls.

Congratulations on what I perceive as a winning essay!

Edwin Eugene Klingman

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Author Ken Wharton replied on Aug. 28, 2012 @ 19:44 GMT
Hi Edwin,

Thanks for the kind words! I'll be looking forward to your comments.

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Frank Makinson wrote on Aug. 25, 2012 @ 17:10 GMT
Ken,

I will agree that the universe is not a computer, but it is my opinion it has more complicated interactions than any computer we can imagine.

Pg 8: "We can treat the universe as a global, fourdimensional boundary-value problem, where each subset of the universe can be solved in exactly the same manner, with exactly the same rules."

I notice the term "subset" appeared once...

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nmann replied on Aug. 25, 2012 @ 18:52 GMT
He's at SETI.

Friedemann Freund

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Peter Lynds replied on Aug. 26, 2012 @ 00:10 GMT
Great essay Ken. You're making some very good noises there--of the type that ring true (and dare I say it, make sense). Best of luck in the contest.

Peter

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Author Ken Wharton replied on Aug. 28, 2012 @ 19:52 GMT
Thanks, Peter -- good luck to you as well.

Frank, I'm afraid I don't really follow much of your comment, but good luck developing your ideas. Friedemann is an adjunct faculty member in our department, but he doesn't teach here, and is mostly at SETI. He's working on some very interesting things these days...

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Armin Nikkhah Shirazi wrote on Aug. 26, 2012 @ 03:02 GMT
Dear Prof. Wharton,

I found your essay to be very original, and particularly the fact that it pointed out some aspect of our deepest understanding that I was not aware of was particularly refreshing.

It appears to me that your view of the LSU implies a "block universe" but I did not see any remark to that effect. Is that correct? If that is the case, does it also open the door to violations in causality? Finally, it seems to me that an acceptance of an LSU interpretation of entanglement "rationalizes away" the conceptual difficulties it poses. Should we not be careful that we don't "give up to soon" before we can find an explanation of a puzzling phenomenon?

I found it interesting that on two tangential points your essay and mine have complete agreement:

The notion that there are still hidden forms of anthropocentrism embedded in our current worldviews, and that the Path integral formulation provides a more fundamental way of understanding quantum mechanics. I hope that you may find the time to take a look at my essay and provide constructive feedback and criticism. I'd particularly appreciate your perspective on whether your think that some of the ideas in there are more in accord with the NSU or the LSU.

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Author Ken Wharton replied on Aug. 28, 2012 @ 20:16 GMT
Hi Armin,

Yes, the LSU assumes a block universe, but so does the NSU and all of modern physics, as I see it. (With the exception of the measurement problem as applied to the standard quantum state; for more on this telling mismatch you'll have to dig up my entry to the very first FQXi contest.)

Denying a block universe is basically saying that we're parameterizing physics all wrong, and we shouldn't have functions that look like the classical Electric field E(x,y,z,t), but instead things like E(x,y,z,t_clock,t_obs), where t_clock is usual time and t_obs is the time at which one is discussing E. Maybe someone will develop such a physical theory, but until they do, physics assumes a block universe.

As for your second question, it depends on what you mean by "violations in causality". See the recent piece on my work with Huw Price.

Also, I'm not trying to "rationalize" away entanglement -- I'm trying to come up with a spacetime-based LSU model that quantitatively yields all of the same correlations as the standard configuration space version. I don't have it yet, but there are no conceptual show-stoppers. As for whether I'm 'giving up too soon'... I'm actually just exploring an alternate path towards the same goal. I don't think the century-old NSU-approach to quantum phenomena would suffer if a few researchers headed off in a new, promising direction. :-)

If your entry concerns the path integral, I'll put it near the top of my to-read-list... Thanks for the pointer!

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Michael Silberstein wrote on Aug. 26, 2012 @ 20:02 GMT
Hi Ken, here are the passages from your essay to keep in mind for the comments below:

If one wants to place quantum theory into the spacetime of GR,

one must use the Lagrangian Schema, solving the

problem "all at once". Only then can the solution

take into account the actual future measurement

which, recall, is imposed as a boundary constraint

on L. So an...

view entire post


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Author Ken Wharton replied on Aug. 29, 2012 @ 04:55 GMT
Hi Michael,

Yes, lots of points of agreement. But let's take the disagreements one point at a time.

First, you bring up the block universe. This is a red-herring that has little to do with NSU, LSU, or anything directly related. In my mind, the arguments against the block universe (arguments for presentism, or the growing block) are simply are not consistent with SR, GR, or how we...

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Michael Silberstein replied on Sep. 2, 2012 @ 05:11 GMT
Hi Ken,

First, regarding your essay. Title not withstanding, you are not really arguing against the universe as literally a computer a la Lloyd or Wolfram. You only indirectly argue against them by positing a block universe, which certainly can’t be computed. So my questions were about trying to pin down your main conclusion. Now, you admit in your reply to me that you don’t have a...

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Author Ken Wharton replied on Sep. 4, 2012 @ 22:50 GMT
Hi Michael,

> Title not withstanding, you are not really arguing against the universe as literally a computer a la Lloyd or Wolfram. You only indirectly argue against them by positing a block universe, which certainly can't be computed.

I'm not sure I'm reading that correctly; surely you're not saying that there are no block universes that can be computed? Wolframs universes are...

view entire post


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Yuri Danoyan wrote on Aug. 28, 2012 @ 19:12 GMT
Dear Dr Wharton

First quote from your essay: "The LSU blends time and space together just

like GR, while the NSU has to grapple with a dynamic evolution that seems to single out time as\special".

In my essay I write about this issue ,but contrary.

See my letter to Dr Stephen Weinberg.

http://fqxi.org/community/forum/topic/1413

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Author Ken Wharton replied on Aug. 28, 2012 @ 22:26 GMT
Hi Yuri,

I think I disagree with Weinberg's response to your interesting question -- I don't think that you can discretize space while not discretizing time, at least not in any GR-friendly way.

That said, I'm not a particular fan of discretization at all -- at least not the conventional justifications for it. (That was the last essay contest, which I linked to above.)

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Yuri Danoyan replied on Aug. 28, 2012 @ 22:45 GMT
My essay devoted at first to splitting space from time.

GR-is not completed theory,as SR.Why i must be friendly to her?

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Author Ken Wharton replied on Aug. 29, 2012 @ 05:00 GMT
You certainly don't have to be friendly to GR or SR -- many quantum theorists take the same view.

For me, I guess I just have too much respect for Einstein's hard-won insights, and too little respect for our human intuitions about time.

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Dan J. Bruiger wrote on Aug. 29, 2012 @ 14:58 GMT
Dear Professor Wharton,

Thank you for your eloquent essay. As I am one of those lay persons for whom the Lagrangian approach is "non-intuitive", I can't pretend to follow all of your arguments in its favor. Yet, your criticisms of the Newtonian approach seem clear enough to me. My corresponding thought is that the laws of physics are algorithms summarizing, after the fact, empirical data. One tends to forget that, in favor of a notion that they have some independent causal power to "determine" the future. This is so only to the extent they can be extrapolated to new situations. Otherwise, 'determine' can mean only the human sense in which one does one's best to determine what is, or will be, the case, or will be observed. In other words, dynamical equations do not have causal power and do not describe determinism in nature, only the logical determinism that belongs to mathematical systems, which are products of definition. Whether the sample of data used to fit the equation to reality consists of an 'initial condition' (NSU) or of 'boundary condition' (LSU) seems to me irrelevant to this point, though there may be, as you say, advantages to the latter approach.

In any case, it seems common sense that the universe can "compute itself" only in the trivial sense that it is an analogue of itself—an "analogue computer". Even if the universe is ultimately discretized, in no way can we assume that it is a digital computer that "processes information" in the way that our computers do, obeying the laws of physics as a computer obeys its program. Such beliefs are but the worst sort of anthropomorphism, embracing current technology as the metaphor for reality. But that is nothing new in physics, which early embraced clockworks and machines as models, and now the computer as universal machine.

Dan

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Author Ken Wharton replied on Sep. 4, 2012 @ 20:01 GMT
Hi Dan,

I agree that the usual focus on empirical data is one way that anthropocentrism finds its way into foundational arguments. But I didn't mean to imply that it was inherently impossible to map useful mathematics to reality. After all, *something* must determine the patterns we observe in the universe – it's not a random block of events. Still, I agree that this "something" is probably not the dynamical equations that we find so empirically useful. (And note the LSU does not merely put boundary data on such equations, but operates at a higher level than the equations themselves. In principle, the LSU can work without dynamical equations at all.)

Also, I trust you noticed that my main argument is completely distinct the analog/digital issue (for my views on that issue, see the previous contest). My main argument here is that the universe is not even an analog computer, at least not one that is governed by the 3-step Newtonian Schema.

Best, Ken

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Avtar Singh wrote on Aug. 30, 2012 @ 17:12 GMT
Dear Ken

First of all it’s great to know that we are neighbors living in San Jose. I also have been a part-time lecturer at San Jose State in the past and have several faculty friends there. I would like to get in touch with you and meet you if you would like to share the mutually beneficial results of our work.

Your conclusion –“The universe is not a computer” is fully...

view entire post


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Author Ken Wharton replied on Sep. 4, 2012 @ 20:26 GMT
Hi Avtar,

On a quick scan, I'm afraid I can't find the connection between our essays, but I'll shoot you an email and see if we can cross paths this semester.

Cheers, Ken

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Anonymous wrote on Aug. 31, 2012 @ 00:58 GMT
Dear Ken

Nice essay. I hadn't before given much thought as to why most physicists do not

like the idea of future boundary conditions. I like your anthropic explanation.

From reading some of your other work it seems you are mostly interested in Lagrangian field theory rather than Lagrangian mechanics. For this reason, I'm curious to know how you imagine describing an electron?

If you imagine the electron as being a soliton, then we agree on that. On the other hand, I think that looking for a nonlinear field theory of the electron is jumping way too far ahead in terms of our current knowledge of physics because the length scales are too small. The experimental bounds on detecting internal structure of the electron charge-center suggest it would be a rather small soliton (< 10^(-19)m), which is an awful lot smaller than the electron Compton wavelength and I think too small to be relevant in quantum mechanics.

So the way I imagine future boundary conditions most directly playing a role is through Lagrangian mechanics (2nd or higher order) not field theory. I touch on this in my essay (briefly in Section 2.1). Hope you find it interesting.

Good luck with the essay!

Andrew

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Author Ken Wharton replied on Sep. 4, 2012 @ 21:53 GMT
Andrew,

It's great to see someone else pushing two-time boundary approaches to quantum problems... Section 2.1 definitely made me want to read more, and I hope to get to it soon. If you have any other drafts or preprints on this general topic, I'd love to take a look; please feel free to send them to me at whartonscience.sjsu.edu.

The continuous/discrete issue is an important one,...

view entire post


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Harlan Swyers wrote on Sep. 1, 2012 @ 21:52 GMT
Ken

I like your paper, and think that this issue of the universe being or not being a computer is important. I don't think there is any conflict if we say that evolution of the wave function is deterministic. So its not so much that there are future boundary conditions, its that we can know some probabilities with certainty. We know that we are mortal for instance. We can not escape the unbearable certainty of some outcomes. There are certain two state systems.

Determinism is a tricky thing. There are two types that I can articulate, one is cold determinism of the classical, and the other is the warm determinism of the quantum. Determinism is a foundation it seems, but the universe seems to prefer the latter over the former.

In any case, it seems that you would agree with the statement that quantum universe is certainly more relevant than the classical one, would you agree?

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Author Ken Wharton replied on Sep. 4, 2012 @ 22:06 GMT
Hi Harlan,

I don't much like the concept of "warm determinism"... I think (to paraphrase Jaynes) that's just scrambling together subjective and objective elements into a conceptual morass. If there's *any* part of the chain between measurements that's uncertain, why wouldn't you expect the whole length of the chain to be smoothly-uncertain? Why push all the uncertainty to the very end, at the moment when it makes the least physical sense?

As for your question, I'm not sure I can answer that without knowing what you mean by 'quantum universe'... There certainly shouldn't be two independent sets of physical theories, one applying to the microscopic world and one applying to the macroscopic. But I happen to think that the ultimate fundamental theory (which would govern both micro- and macro-) will in many ways look a lot more like classical Lagrangian field theory than standard quantum mechanics. We'll see... :-)

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Member George F. R. Ellis wrote on Sep. 3, 2012 @ 16:05 GMT
Dear Ken

very nice thoughtful essay, one of the best. A comment: I am a little surprised you do not mention Aharanov's "two-time" formalism (see for example this paper and references therein), as it seems very close to what you are proposing as regards the way time works.

As regards the LSU formalism, this non-local approach is very interesting. You state "Instead of initial inputs (say, position and angle), Fermat's principle requires logical inputs that are both initial and fi nal (the positions of X and Y). The initial angle is no longer an input, it's a logical output."

Yes indeed. What this approach does is very interesting: it puts dynamics into a framework that resembles the process of adaptive selection (the dynamics is offered a variety of choices, and selects one that it finds optimal according to some selection criterion, rejecting the others). This kind of process occurs in various contexts in physics, even though this is not widely recognised; for example it underlies both Maxwell's demon and state vector preparation (as discussed here ). I believe there may be a deep link to the dynamics you describe. This may be worth pursuing.

George Ellis

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Author Ken Wharton replied on Sep. 4, 2012 @ 22:24 GMT
Hi George,

Thanks for the nice comments. I'm a bit of two-minds about the two-state formalism (:-) ... It's certainly a step in the right direction, with many elements that I like. But it's built so firmly on the standard QM foundation that it inherits too many of QM's traditional problems -- despite the fact that the retrocausal elements can in principle solve many of those same problems.

The biggest technical problem it inherits is the configuration-space of the standard quantum state. This isn't so evident in many of the papers as they usually only talk about single-particles, but if you delve into the details it only works if *both* the history- and the destiny-vector live in configuration space.

Now, these latest papers you mention are a step in the right direction, trying to fit entanglement experiments back into spacetime -- I was very pleased to see them when they were posted. But it's impossible to do this analysis in the traditional two-state formalism, because of the configuration-space problem. Basically they're pointing out what Huw Price and I have been arguing all along -- that the retrocausal elements can bring configuration space back to spacetime. But, by its very nature, the two-state formalism is not the right framework to accomplish this -- one needs something that departs from standard QM more radically.

I like the "adaptive selection" phrase, and might even use it as an easier-to-understand 3+1D description for the 4D physics I'm proposing. I'll be looking forward to reading both that preprint and your essay, which appears to be getting some very favorable feedback.

Cheers,

Ken

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Member George F. R. Ellis replied on Sep. 5, 2012 @ 06:15 GMT
By the way I forgot to say that I totally agree with your critique of the idea of the universe as a computer. It's a totally overstretched analogy. And what is quite interesting is that if you analyse the flow of causality in computers, they are a classical case of top down action (I sketch this in my own essay). What drives them is the logic of the algorithms they employ - which are abstract entities.

Cheers

George

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Member Ian Durham replied on Sep. 23, 2012 @ 02:32 GMT
I actually agree with George on this point (you should see some of the interesting comments on his very stimulating essay, as well as those on Julian Barbour's - conversely, my own essay seems to be about the only defense of reductionism in this entire contest!).

Ian

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Inger Stjernqvist wrote on Sep. 4, 2012 @ 16:45 GMT
Hi Ken,

I'm very relieved that the Universe is not a computer! Sure, I need to re-read your essay many times to only partly understand it. But I need not know all the rules of hockey to see that a game is brilliantly played.

Best regards!

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Author Ken Wharton replied on Sep. 11, 2012 @ 20:22 GMT
Thanks, Inger, for the kind words!

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Eugeniu Alexandrescu wrote on Sep. 5, 2012 @ 23:53 GMT
Dear Dr Wharton,

Your essay is clearly heading in the right direction. But, should this discussion stop at the physical aspect of the spacetime, which is still derived from a mathematical framework? Or have we missed the big picture precisely because of an even deeper bias we have about the spacetime at its most fundamental -- and physical -- level?

In my essay I introduce a model of the universe that resides entirely in ordinary spacetime. In this model, quantum spaces are explained as real but independent spaces, similar to the space of the universe.

However, something is less than ordinary: the hypothesis about the nature of this wrong assumption, which changes the way we see reality. Surprisingly, the hints about this wrong assumption were provided by Minkowski himself, but the scientific community ignored them for the last century.

Cheers,

Gene

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Author Ken Wharton replied on Sep. 11, 2012 @ 20:35 GMT
Gene,

There certainly may be other anthropocentric biases built into physics, and it also is true that I only experience this one universe, so that might unfairly bias me against your ideas.

That said, as a physicist, I want to explain the particular universe that I observe. Maybe it will turn out that the best explanation will require the use of other places and times outside "my universe", but I can't see myself seriously pursuing that possibility until I've ruled out some simpler options.

Here's a quote I still kind of like from my entry to FQXi's very first contest:

"Looking to quantum theory for answers about spacetime is like looking to a roadmap for answers about geology: it's a tool designed for something else entirely. In general, quantum theory tells us nothing about spacetime except what its formulators put into it in the first place."

Best, Ken

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Anonymous wrote on Sep. 7, 2012 @ 12:20 GMT
Great essay, Ken. Had it been posted early enough, we would've made yours a prerequisite for ours and detailed how we satisfy your desideratum for an LS-only approach to new fundamental physics. Unfortunately, it wasn't in the blockworld cards so (with your permission) I'll have to do so here.



If you're interested in new LSU-inspired approaches (LS formalisms) to fundamental...

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Author Ken Wharton replied on Sep. 11, 2012 @ 20:37 GMT
Hi Mark,

Yes, you and Silberstein are further along than any other LSU-style approach that I know of, and it's great to see some new cosmological results coming out of it. For now I hope we can agree to disagree about the continuum/discrete issue, and keep finding points of contact, such as this essay. More to come...

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Richard William Kingsley-Nixey wrote on Sep. 7, 2012 @ 21:38 GMT
Ken

Beautiful essay, and a very good point to get across. I hope you can get to read my own, and commend you to the other I refer therein, and particularly the Jackson and McEachern essays, the first for the mechanisms, both that and the second with some extended proof of your appraoch.

Interesting times!

Well done.

Rich

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Author Ken Wharton replied on Sep. 11, 2012 @ 20:53 GMT
Rich,

Thanks for the kind words -- although I think both you and Jackson may be misreading my main point to some extent. From what I can tell about your essay (and Jackson's, and McEachern's), you're still working in a conceptual framework aligned with the NSU. If there's some LSU approach buried in any of those essays, I must have missed it, but I'm certainly interested in any such efforts.

Best, Ken

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Mark Stuckey wrote on Sep. 8, 2012 @ 15:49 GMT
Ken,

I've been trying to put my finger on what strikes me as inconsistency in your desiderata. Perhaps you can help me understand where I'm missing the boat.

Desiderata: An LS formalism that does not admit an NS formalism but does admit a (3+1)D continuously mediated story between Source and sink that explains the measurement outcome.

My confusion: The way one obtains NS from LS is to demand the extremum condition of LS be satisfied instant by instant. This leads to the local as well as global conservation of some property or characteristic of the fields involved; in classical physics it's energy and in quantum physics it's probability. Thus, in order to avoid an NS characterization of your ultimate LS formalism, there can be nothing conserved instant by instant. But, if no field property or characteristic -- absolutely *nothing* -- is locally conserved, what *is* being mediated in a (3+1)D continuous fashion?

I can imagine a field filling spacetime between initial and final hypersurfaces (and therefore between the worldtubes of the equipment). This field has some 4D global property that satisfies an LS constraint, but this field does not possess any property or characteristic that satisfies any constraint instant by instant (for any foliation). Trying to mathematically model such a field strikes me as a perfectly reasonable thing to do (it's what we're doing graphically). But, the very field property that rules out the possibility for an NS formalism also rules out the possibility of a (3+1)D story. At least, that's the way it strikes me. Perhaps you can dispel my confusion :-)

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Author Ken Wharton replied on Sep. 11, 2012 @ 21:08 GMT
Hi Mark,

I'm not sure if by "story" you mean "explanation" or mere "description"... If the former, we're not on the same page: LSU explanations don't make much sense when viewed sequentially in 3+1D -- they require 4D "stories". But I'll assume you're merely using "story" to refer to my hoped-for-3+1D representation of what is happening between measurements.

As for whether giving up NS for LS means that *nothing* can be conserved instant-by-instant... That seems way too strong a conclusion. After all, there are aspects of Noether's theorems that provide conservation-type-rules (from the symmetries of the Lagrangian) even if the Euler-Lagrange equations are not strictly adhered to. There's a nice paper by Harvey Brown to this effect...

If you ask me about ontology, "what is being mediated", my best guess right now is the classical Lagrangian density itself, and the classical fields that comprise it. (Bearing in mind that those fields need not strictly adhere to the Euler-Lagrange equations, just as single-photon experiments obviously don't adhere to Maxwell's equations.)

On your last point, perhaps the problem is what you mean by "story" (see first paragraph above). Otherwise, I think we're on the same page. Also, note that LS approaches can give meaning to *new* instant-by-instant constraints, that don't make any sense in an NS framework -- such as enforcing a zero total Lagrangian density throughout spacetime (to pick a not-so-offhand example... :-).

Cheers, Ken

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Mark Stuckey replied on Sep. 13, 2012 @ 22:09 GMT
Thanks for the reply, Ken.

I'm trying to understand your desiderata, so I'll go with "my hoped-for-3+1D representation of what is happening between measurements." :-)

My questions are an attempt to understand what you mean by an LS approach that doesn't allow for an NS approach but nonetheless allows for a 3+1D representation. Specifically, I'm interested in how that might be mathematically instantiated.

In order to avoid a time-evolved differential eqn (NS approach), the LS constraint cannot be satisfied instant by instant. Your response seems to agree with that, so no confusion there. Also, it seems to me, L cannot have any symmetries since they lead to conserved currents cast in conservation equations, i.e., NS formalism. Thus, L has no symmetries and satisfies a global constraint that cannot be satisfied instant-by-instant, yet this formalism allows for a 3+1D representation.

Maybe it would be more productive to ignore my confusion and share your specific idea(s) for how this might work. I realize you don't have a finished product, so I don't expect anything precise. You allude to an idea at the end of your essay, so perhaps you could elaborate a bit on that.

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Author Ken Wharton replied on Sep. 18, 2012 @ 17:02 GMT
>In order to avoid a time-evolved differential eqn (NS approach), the LS constraint cannot be satisfied instant by instant.

Ah, here's the point of confusion. In any given instance, between any two particular measurements, I see nothing wrong with the intermediate fields obeying *some* continuous constraint. After all, I expect the fields to be smooth/continuous themselves.

Here's an example (not actually what I'm going for, but useful for this discussion): Suppose a photon/EM-field in a double-slit experiment is a continuous field, with LS rules constrained by both the past preparation and the future measurement. This 4D story can be represented as a 3+1D description, but different future measurements could easily have different past behavior. So in 3+1D the field might obey differential equation A if future boundary/measurement A' is imposed (corresponding to an interference measurement), but would instead obey differential equation B if future boundary/measurement B' is imposed (corresponding to a which-slit measurement). So there's no master differential equation and NS fails as an "explanation". And yet, both A and B might conserve the same quantities, so one still gets the behavior that you're worried that LS rules out. Does that sound reasonable?

Right now my research is taking me more towards something that roughly maps to stochastic quantum mechanics (esp. Larry Schulman's ideas, if you're familiar with his non-classical 'kicks'), where 'conserved' quantities are only conserved on average, in some statistical limit. But I see nothing fundamentally wrong with the approach in the previous paragraph, as an example of how LS might not map to an NS story.

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Phil Warnell wrote on Sep. 8, 2012 @ 17:39 GMT
Dear Prof. Wharton,

I very much enjoyed the essay and realize you are looking at this from primarily a mathematical perspective as it relates to the physics more so than from the philosophical bend. Never the less once the Lagrangian perspective is taken it's hard not to wonder about what it all means as opposed to simply what observable results it has mandated. That is while...

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Author Ken Wharton replied on Sep. 11, 2012 @ 21:28 GMT
Phil,

Yes, lots of great philosophical questions at the heart of this stuff. Usually I just point people to Huw Price at this point, but I'll venture a few comments of my own.

Very nice quote about Fermat's principle, but if you'll look closely, the claim that "nature... acts without foreknowledge" is precisely the NSU assumption that the universe is just as limited as us humans. ...

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Phil Warnell replied on Sep. 16, 2012 @ 12:07 GMT
Dear Prof. Wharton,

Thanks for your reply as it clarifies for me what an LSU presents for you as being within a broader context. As to your last remark that it requires one to "relax the Principle of Sufficient Reason to the point where our universe is just one of many possible solutions to the same ultimate constraints" leaves me somewhat confused. That is are we talking about LSUs...

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Amanda Gefter wrote on Sep. 12, 2012 @ 04:10 GMT
Hi Ken,

I really enjoyed your thought-provoking essay. I'm wondering how your idea fits in with Hawking and Hertog's top-down cosmology?

Thanks for a great read.

Cheers,

Amanda

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Author Ken Wharton replied on Sep. 14, 2012 @ 04:16 GMT
Hi Amanda,

Glad you liked it, and thanks for the interesting question. Before your post, I had only read summaries of 'top down cosmology', and it originally struck me as making the time-reverse of the usual mistakes when it came to interpreting the wavefunction. But after your comment, I went back and read some of the original papers. I was pleasantly surprised to find that much of...

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Anonymous wrote on Sep. 12, 2012 @ 11:06 GMT
Ken, you never disappoint. Your surgeon's skill for dissecting critical assumptions not only exposes the real meaning behind them -- you underscore by example the truth of Jacob Bronowski's aphorism, "All science is the search for unity in hidden likenesses."

The biased question -- "Doesn't Bell's Theorem prove that quantum correlations can't be caused by past hidden variables?" -- has indoctrinated a generation with the belief that the world is reduced to computation alone, that no local (read classical) theory is capable of continuous correlation of measurement values.

I love your statement, "Now there's one last anthropocentric attitude that needs to go, the idea that the computations we perform are the same computations performed by the universe, the idea that the universe is as 'in the dark' about the future as we are ourselves."

That is why I like Joy Christian's topological framework -- although not directly related to your Lagrangian schema, it does also " ... treat the universe as a global, four-dimensional boundary-value problem ..." in a continuum of correlated values, and in which Nature has a choice.

I hope you get a chance to visit my essay ("The Perfect First Question") that incorporates Wheeler's information-theoretic philosophy into a framework of continuous measurement functions.

Thanks for a great read -- and best wishes in the contest!

Tom

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Thomas Howard Ray replied on Sep. 12, 2012 @ 11:08 GMT
Sorry, must have been logged out. The above is mine.

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Author Ken Wharton replied on Sep. 14, 2012 @ 04:17 GMT
Hi Tom,

Thanks for the very nice comments! I'm way behind on reading essays, but I've added yours to the list... That's interesting about the connection you see with Joy Christian's work; I haven't yet put in enough effort to wrap my head around it, perhaps because I'm stuck in too much of a classical-spacetime mindset.

Cheers!

Ken

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Fred Diether replied on Sep. 23, 2012 @ 00:10 GMT
Hi Ken,

Very good essay and after reading it I must strongly urge you to study Joy Christian's "Disproof of Bell's Theorem" (Most of the book is also on arXiv.org as the separate chapters). Joy's model is a physical model that has so far completely resisted any kind of computer simulation while completely explaining the correlations seen in EPR-Bohm type scenarios. Granted, his model is a bit difficult to understand at first but once you understand some basics about Geometric Algebra, the model is actually fairly simple. Nature simply has a 50-50 chance of left or right handed orientation when the particle pairs are created. Now, I hadn't really thought about it before but it might be nice to try to fit the model to LSU.

Also, if you have a chance, you can check out my essay where I briefly argue that quantum mechanics is due to relativistic effects on the microscopic scale.

Best,

Fred

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Michael Popov wrote on Sep. 12, 2012 @ 14:59 GMT
Dear Ken,

Your passage

"Is the universe ebectively a quantum computer?

This essay argues "no" on both counts; we have erred by assuming the universe must operate as some corporeal image of our calculations "

suggests some sort of attitude to mathematical details of so-called "quantum computer" and "the universe as approximation to quantum computer ".It is easy to know that quantum computer today is merely mathematical construction based on ideas of complex numbers algebra, where qubits, algorithms and Hilbert complex vector space are used to imagine such sort of software for future super computer (used by NATURE as well ). Some theorems of complex computational mathematics could be used in philosophy of the Universe as a whole, indeed.But,unfortunatelly, we cannot deduce any serious technical content from such poetical image as " Universe as Computer "(probably inspired by the art of the Enlightment) indeed. I suppose there is no real cognitive problem here...?

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Author Ken Wharton replied on Sep. 14, 2012 @ 04:21 GMT
Michael,

Actually, I'm being much more heretical than you suggest. I'm not saying that we can't physically reproduce nature's computations, I'm saying that nature doesn't even *utilize* computations, at least not in the standard past-to-future sense of the word. I'm denying any map between reality and Hilbert space, as well as the premise that you're assuming when you say "used by NATURE as well". (I'm using nature=universe here, although I use only 'universe' in the essay.)

Hope that makes it sound a bit more interesting... :-) And yes, I do propose an alternative path forward; I'm not just pointing out unresolvable problems.

Best,

Ken

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Yuri Danoyan wrote on Sep. 13, 2012 @ 00:15 GMT
You wrote:

"Which past events cause

the future boundary constraint? How do objects in

the universe \know" what future boundary they're

supposed to meet? Doesn't Bell's Theorem [13] prove

that quantum correlations can't be....."

All your statements based on light speed constant c

Imagine please our universe this way

Big Bang; Present; Big Crunch

c=10^30; c=10^10; c=10^-10

G=10^12; G=10^-8; G=10^-28

h=10^-28; h=10^-28; h=10^-28

alfa =10^-3; 1/ 137; 1

e=0,1 ; e=e ; e=12

What is your question to this picture?

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Author Ken Wharton replied on Sep. 14, 2012 @ 04:22 GMT
Yuri,

You picked out the one group of sentences that I was setting up as straw men, as bad arguments that I don't agree with, to complain about.

I'm happy with a constant speed of light, but that's completely beside the point of my essay.

Ken

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Yuri Danoyan wrote on Sep. 13, 2012 @ 12:58 GMT
Dr.Wharton

Are you superdeterminist?

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Author Ken Wharton replied on Sep. 14, 2012 @ 04:23 GMT
No, I'm not; I agree with Huw Price on this issue.

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Yuri Danoyan replied on Sep. 18, 2012 @ 14:22 GMT
What is your evaluation Gerard 't Hooft article?



Discreteness and Determinism in Superstrings ?

arXiv:1207.3612 (replaced) [pdf, ps, other]

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Torsten Asselmeyer-Maluga wrote on Sep. 14, 2012 @ 11:33 GMT
Dear Ken,

very nice essay. I completely agree with you about your claim: teh universe is not a (quantum) computer. Determinism has influenced physics sine a long time. But non-local phenomena arise (like EPR), so we have to go deeper and find models to include te indeterminism. Hidden variables are no real path but non-computability is a way. What I mean are real non-algorithmic real numbers. By definition there is no algorithm (or law) to calculate them but they exists. So, if our future is non-computable then we keep up the concept of the free will etc. But as a consequence we need the contiuum (probably you do not like this point). One reason, why I keep up the concept of a smooth manifold.

If you like, have a look into my essay.

Best

Torsten

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Author Ken Wharton replied on Sep. 23, 2012 @ 20:42 GMT
Torsten,

Thank you for the comments... I actually quite like the continuum, although that probably didn't come across in this contest (see the last contest for more details). The question of whether EPR/Bell-inequalities can be explained by hidden variables or not actually depends on whether one is in an NSU or LSU framework. It works in the latter but not the former. Unfortunately, most analysis simply assumes NSU, which has biased many people against hidden variables, but that option opens up again with LSU.

Best,

Ken

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James Lee Hoover wrote on Sep. 20, 2012 @ 05:50 GMT
Ken,

You say,

"How would the founders of quantum theory have met these challenges if they thought the universe ran according to the mathematics of the Lagrangian

Schema { not as a computer, but rather as a global four-dimensional problem that was solved \all at once"?"

How about modeling with a quantum computer? Computers are only means to build a complex scenario that mimics a hypothetical situation. You're not saying that some aspect of the universe runs like a computer. With our understanding of gravity's properties, it is a mystery that only empirical evidence seems to address, as I explore in my essay.

Liked your essay. A great deal of substance here.

Jim

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Author Ken Wharton replied on Sep. 23, 2012 @ 20:45 GMT
James,

Thanks! I'm not sure I understand your point, but even if one had a working quantum computer, one couldn't "model" quantum phenomena with it; one could merely "reproduce" quantum phenomena. And, unfortunately, such a computer would give no more information about what was happening between quantum measurements than the bare phenomena themselves, because one can't make an "extra" intermediate measurement in the quantum computer without destroying the match to the actual phenomena in the first place. (Weak measurements aside for now...)

Really, a quantum computer would *be* a quantum phenomenon, in and of itself. It would not be a useful "model", in that it would not add to our understanding... any more than pointing out that a star is an excellent model of that same star would add to our understanding.

Please let me know if I'm totally off-target with your intended comment!

Cheers,

Ken

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Anonymous wrote on Sep. 20, 2012 @ 17:07 GMT
Hi Ken,

We met at PI when you gave your seminar there a couple of years ago and then again at the Foundations meeting in Brisbane. I remember talking to you about the universe being a computer (or rather 'not' being one)! How have you been?

Thanks for the well-written essay. I must say that I wholeheartedly agree with your critique of the universe being a computer and am particularly...

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Sean Gryb replied on Sep. 21, 2012 @ 14:04 GMT
Oops... Somehow I got logged out!! I am "Anonymous"

- Sean Gryb.

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Author Ken Wharton replied on Sep. 23, 2012 @ 20:59 GMT
Hi Sean! Yes, of course I remember you, and thanks for your very thoughtful comments.

Your GR points are all perfectly valid, and you're right that the LSU-style "thick sandwich problem" is unsolved (specifically, the question of whether there is one unique classical solution for a given closed-hypersurface boundary metric, and how to find it). But the "problematic questions" that I had...

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Sean Gryb replied on Sep. 24, 2012 @ 11:43 GMT
Hi Ken,

Thanks for your detailed response! If you have had to a chance to read my essay, you'll probably find that we have very different intuitions for how to address some of these problems (in our approach, we treat configuration space as completely fundamental!). Nevertheless, I am very interested in hearing more about your ideas. I think I can see where you are going and would be interested to see a toy model worked out.

In regards to the "thick sandwich" problem, I can see now why the classical result doesn't bother you. However, our universe seems pretty classical now. It takes some real mental gymnastics to try to think in the way you are suggesting!

Where our intuitions do seem to overlap is with the Oracle issue. Even in the setting described in my essay, I think this is potentially the only way to really understand measurement although I didn't really say this in the text. I would be happy to discuss ways to make this idea more concrete. I've always found it very intriguing.

Hope to see you some time again!

Cheers,

Sean.

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Yuri Danoyan wrote on Sep. 22, 2012 @ 21:43 GMT
The computer and the universe

John Archibald Wheeler

Abstract

The reasons are briefly recalled why (1) time cannot be a primordial category in the description of nature, but secondary, approximate and derived, and (2) the laws of physics could not have been engraved for all time upon a tablet of granite, but had to come into being by a higgledy-piggledy mechanism. It is difficult to defend the view that existence is built at bottom upon particles, fields of force or space and time. Attention is called to the “elementary quantum phenomenon” as potential building element for all that is. The task of construction of physics from such elements is compared and contrasted with the problem of constructing a computer out of “yes, no” devices.

Preparation for publication assisted by the University of Texas Center for Theoretical Physics and by National Science Foundation Grant No. PHY78-26592.

http://www.springerlink.com/content/ck753337h051
5573/

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Hou Ying Yau wrote on Sep. 23, 2012 @ 00:25 GMT
Dear Ken,

Although not directly related to your essay presented here, I have an idea that I hope can be of some interest to you base on a realistic model in ordinary space-time. Nothing mathematical fancy, I find that the bosonic quantum field can be reconciled from a system with vibrations in space and time. The model has some unique features that seem to be extendable to gravity and non-locality of quantum theory.

Is there really no reality in quantum theory

Best wishes for you in the contest.

Hou Yau

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Hou Ying Yau replied on Sep. 23, 2012 @ 00:30 GMT
I am also living in the Bay Area and hope I can meet you one day.

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Author Ken Wharton replied on Sep. 25, 2012 @ 03:24 GMT
Hao Yau,

Thanks for the pointer to your essay. I think the clearest connection is that you're interested in the second-order Klein-Gordon equation. For my earlier not-quite-LSU take on this equation, you might see my reference [8]. I've actually backed away from this approach to some extent, but still think Klein-Gordon is far preferable to the Schrodinger equation, and that everyone tends to misinterpret the so-called "negative frequency" solutions by viewing them in the light of a totally different equation. So if anything in [8] strikes a chord with your efforts, let me know and I might be able to at least steer you away from my various failed ideas... :-)

Best,

Ken

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Member Ian Durham wrote on Sep. 23, 2012 @ 02:28 GMT
Hi Ken,

Ha! I finally read it (though I should have done so months ago when you first sent it to me and I do apologize for that).

Anyway, so, in general, I really like the idea (and your writing is impeccable as usual). But I did feel a bit unfulfilled at the end. For instance, it didn't seem entirely clear to me how the LSU approach solves the problem you pointed out in your first footnote: if the universe is (or at least appears to be) time-asymmetric, why are it's laws time-symmetric?

Also, is it really anthropocentric to try Method X, observe the outcomes of Method X and see that they match reality, and then thus assume Method X must be at least partially correct as a model? I mean, the whole point is to match observation and measurement and even in the quantum realm I think that there has to be some kind of objective reality given the fact that the scientific method even exists in the first place (i.e. while we may all view slightly different realities, we clearly have enough in common to allow us to communicate with one another and even to put quantum mechanics to practical use).

Nevertheless, sometimes I wonder if we are even fully capable of non-anthropocentric thinking.

My only other complaint about the essay is related to my usual diatribe about entropy - I hate associating it with "disorder." I see absolutely nothing bizarre about low-entropy early universe (and Max Tegmark agreed with me on this at the last FQXi meeting, albeit quietly - I was not so quiet). But that's just a personal pet peeve of mine.

Ian

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Author Ken Wharton replied on Sep. 25, 2012 @ 03:21 GMT
Hi Ian,

Thanks for your comments! For your first point about time-symmetry, I don't think this is necessarily an NSU/LSU issue at all, as both viewpoints can be consistent with time-symmetry (see NSU classical physics). But LSU is more "automatically" time-symmetric, and in the particular case of QM, NSU approaches are forced into time-asymmetric stories, while LSU approaches aren't. ...

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Jerzy Krol wrote on Sep. 23, 2012 @ 08:33 GMT
Dear Ken,

very fine essay; I have only some general remark/doubt: what is the reason for arguing in favour of so obvious thesis. Let me explain: we know that even mathematics (arithmetics) is not axiomatizable by any quite powerful set of axioms (Goedel theorems) so some simple algorithms do not have definfite answers. Computers are designed such that algorithms yield definite outcomes. That would be very strange, if impossible at all, if the world would be a computer realizing succesfully the algorithms, since even mathematics shows the impossibility of this (for a suitably rich system).

wishes,

Jerzy

c.f.: http://fqxi.org/community/forum/topic/1443 (What if Natural Numbers Are Not Constant?)

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Author Ken Wharton replied on Sep. 25, 2012 @ 03:36 GMT
Hi Jerzy,

I'm glad you think my thesis is obvious, but I wager you're in the minority.

Also it sounds like you agree for quite different reasons than I'm using... Arguing for under-determined universes as compared to determined universes is a somewhat different issue than NSU/LSU. (After all , classical action extremization is an LSU approach that leads to just as a "determined" result as NSU equations of motion.

That said, these days I am on the fundamentally-underdetermined side of the fence, so I guess we agree after all. :-)

Cheers,

Ken

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Pentcho Valev wrote on Sep. 23, 2012 @ 15:37 GMT
Ken,

I wonder what the Lagrangian Schema could do if a theory is inconsistent, e.g. if in general relativity the speed of light is both variable and constant. You wrote:

"If one wants to "fit" quantum theory into the spacetime of GR, one must use the Lagrangian Schema, solving the problem "all at once"."

I am afraid that would be a hopeless procedure:

W. H. Newton-Smith, The rationality of science, Routledge, London, 1981, p. 229: "A theory ought to be internally consistent. The grounds for including this factor are a priori. For given a realist construal of theories, our concern is with verisimilitude, and if a theory is inconsistent it will contain every sentence of the language, as the following simple argument shows. Let 'q' be an arbitrary sentence of the language and suppose that the theory is inconsistent. This means that we can derive the sentence 'p and not-p'. From this 'p' follows. And from 'p' it follows that 'p or q' (if 'p' is true then 'p or q' will be true no matter whether 'q' is true or not). Equally, it follows from 'p and not-p' that 'not-p'. But 'not-p' together with 'p or q' entails 'q'. Thus once we admit an inconsistency into our theory we have to admit everything. And no theory of verisimilitude would be acceptable that did not give the lowest degree of verisimilitude to a theory which contained each sentence of the theory's language and its negation."

Pentcho Valev

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Author Ken Wharton replied on Sep. 25, 2012 @ 03:46 GMT
Hi Pentcho,

I actually quite like GR, but I grant that the details may be wrong. Maybe one needs to add a new field or two, or even a few new dimensions, or even something stranger.

But the point is that GR (and such extensions) are our best models of the structure of our universe. Ignoring this structure when building up a fundamental quantum theory seems reckless.

Best,

Ken

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Pentcho Valev replied on Sep. 25, 2012 @ 06:28 GMT
The inconsistent theory, if adopted, is much more dangerous for science than the false but consistent theory. The latter is easily falsifiable, the former easily overcomes any hurdle, either logical or experimental. Peter Hayes has explained this quite nicely:

Peter Hayes "The Ideology of Relativity: The Case of the Clock Paradox" : Social Epistemology, Volume 23, Issue 1 January 2009, pages 57-78 "In the interwar period there was a significant school of thought that repudiated Einstein's theory of relativity on the grounds that it contained elementary inconsistencies. Some of these critics held extreme right-wing and anti-Semitic views, and this has tended to discredit their technical objections to relativity as being scientifically shallow. This paper investigates an alternative possibility: that the critics were right and that the success of Einstein's theory in overcoming them was due to its strengths as an ideology rather than as a science. The clock paradox illustrates how relativity theory does indeed contain inconsistencies that make it scientifically problematic. These same inconsistencies, however, make the theory ideologically powerful."

Pentcho Valev

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Lawrence B. Crowell wrote on Sep. 23, 2012 @ 18:32 GMT
I think your essay is very interesting and makes a reasonable point. The Lloyd concept of the “quantum cosmic computer” is something which I have gone back and forth on. My sense of the issue is this: a physical system is modeled as a computer when it is convenient to think of it that way. When it is not so convenient then it is modeled by other means.

A Lagrangian model of a physics...

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Author Ken Wharton replied on Sep. 25, 2012 @ 17:20 GMT
Hi LC,

Thanks for the interesting comments.

>A Lagrangian model of a physics system has the initial state and the final state specified. This carries over to the quantum path integral, where the extremization procedure is generalized to a variational calculus on many paths with quantum amplitudes. The analyst is then faced with the task of finding some dynamical process or quantum evolution which maps the initial state of the system to the final state. The analyst will then use what tools they have in their box to solve this problem.

Ah, but this is my point: there may not *be* some master dynamical process that takes the initial state to the final state, so such an analyst that you describe is implicitly assuming a "NSU". Meanwhile, an LSU analyst will have a broader set of tools to use, as the intermediate solution can take the future constraint into account.

>With the universe in total this picture becomes more problematic. If we are to think of an observer as reading the output, there is no boundary region where this observer can read this output without that procedure also being a part of the "computation".

Yes, exactly. In that case I think it only makes sense to think of the end/asymptotic state of the universe as a "logical input" (even though it's a final boundary condition), just as I argue that quantum measurements should be viewed as boundary constraints on subsystems. It would be nice to have a conceptual framework that would work the same way for both subsystems and the universe as a whole.

>The problem of establishing a Cauchy region of initial and final data is much more difficult to work.

You may be interested in my response to Sean Gryb above in regards to the thick-sandwich problem in GR, and Sean's "Oracle"; looking for (unique) solutions to Cauchy-type problems may be more restrictive than is strictly necessary.

Thanks again!

Ken

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Hoang cao Hai wrote on Sep. 23, 2012 @ 18:46 GMT
Dear professor Ken Wharton

Mathematics as a magic sword have most powerful, but the consequences caused by it does not depend on it.

Kind Regards ! Hải.Caohoàng of THE INCORRECT ASSUMPTIONS AND A CORRECT THEORY

August 23, 2012 - 11:51 GMT on this essay contest.

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Member Hector Zenil wrote on Sep. 23, 2012 @ 21:12 GMT
Dear Ken,

I think there is a conflation between computational models and mathematical representations. It is true that mathematical representations almost always turn out to be computable models, specially when used numerically to approximate the solution to a real-world problem. But a mathematical model doesn't always come with its implementation (in fact rarely does). That is, one has to find a computer implementation for a mathematical model. There is no one-to-one correspondence between models and algorithms. For example, many Turing machines can compute the same computable function, but each can do so in a completely different way (e.g. a function that can be computed in linear time can also be computed in exp time).

While I may agree that the working assumption of science is that nature is mathematical I think it is far from obvious that science assumes that a particular implementation of a mathematical model is the specific way nature operates. This is also a common conflation when people think that saying that a natural process is Turing computable means that it is computed exactly by something like a Turing machine (nobody thinks the brain is a Turing machine, but most science works under the assumption that the brain is Turing computable, which is completely different). In your essay you point out Seth Lloyd's claim that the universe is a computer, this illustrates my point, because in fact Seth Lloyd does not think that the universe is a Turing machine, but in fact a quantum computer, which in the light of your own arguments I find difficult to reject.

On the other hand, I don't think that physicists will ever be able to close all loopholes in quantum theory at the same time, and it hasn't yet been done. While your ideas are provocative I still find the computable ground less subject to particular interpretations.

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Author Ken Wharton replied on Sep. 25, 2012 @ 17:23 GMT
Hector,

We're in complete agreement on your first point: there's no guarantee that models will map to a particular implementation. But to me, that's all the more reason to not limit ourselves to models that are only computable via some temporally-linear fashion (where the algorithm is completely blind to its eventual output).

As for your statement, "I think it is far from obvious that science assumes that a particular implementation of a mathematical model is the specific way nature operates.", I also agree, and think Spekkens' essay makes some useful points in this regard. But if you replace the word "particular" with "Newtonian Schema" (as defined in my essay), I think the situation changes. To me, anyway, it's become strikingly obvious that most scientists assume the only models worth considering are those that might have temporally-linear algorithmic implementations. Meanwhile, promising LSU-style models, which have no such implementation, are not explored.

As you say, the proof will be a "loophole"-free implementation. I just hope that if such a model is developed, it won't be ruled out merely on the grounds that it's not in an NSU framework.

Best,

Ken

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M. V. Vasilyeva wrote on Sep. 23, 2012 @ 22:32 GMT
Dear Prof. Wharton,

as a physicist, you argue that the universe is not a computer. As a professional in the field of computers, it is hard for me to agree with you. To me the universe appears as an enormous computer and I find the parallels between the two everywhere, from the the structure of space with the visible universe confined to a 3-dimensional display, akin to a 3D touch screen, to...

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Edwin Eugene Klingman replied on Sep. 23, 2012 @ 23:24 GMT
Dear M. V. Vasilyeva,

Perhaps were you a little older, and had experience with analog computers, you might not jump to such conclusions.

You say, "In contrast, you physicists seem a headstrong bunch."

But when your only tool is a hammer, everything looks like a nail. When one is mostly familiar with computer concepts, they seem to apply everywhere. Believe me, there's much more to it than you seem to see.

"And so I find it ironic that the modern day physicists appear unaware that their phenomenal ability to compute could in fact be the vestiges of our very origins as well as the origins of our universe. Arguing that the universe is not a computer you physicists don't seem to appreciate the fact that mathematics divorced from the understanding of the underlying reality, and the vision that comes with it, is what has turned you into the glorified calculators and thus put forth the question of your own utility to the rest of the humanity."

Since I have been far more professionally successful in the field of computer design (see here) than as a physicist, and have published university texts on computer design and a dissertation on an 'automata theory' of physics, I do know about computers. All I can say is that, no matter how much everything looks like a nail to you, it's a little deeper than that.

But I still enjoyed your essay.

Edwin Eugene Klingman

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M. V. Vasilyeva replied on Sep. 25, 2012 @ 01:30 GMT
Mr. Klingman,

glad you enjoyed my essay. I see that you are a prolific author and you consider yourself an authority in both physics and computer hardware. And you think that my view on the universe as an immense computer is not deep enough. Well, your opinion of my view is based on an assumption that has no basis in reality. For your information, I started to entertain this idea only after I studied biology and physiology long enough to became convinced that life is a program. Once you make this leap, everything else follows logically.

So I understand very well how you, having never studied life sciences, may have difficulty coming to the same view. Knowing physics and computers may not be enough to come to this conclusion, just as it was not enough for me until I took on biology.

Take care!

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Edwin Eugene Klingman replied on Sep. 25, 2012 @ 05:10 GMT
Ms. Vasilyeva,

Quite an assumption: "So I understand very well how you, having never studied life sciences, may have difficulty coming to the same view."

You are correct that I have not published any books on the life sciences, but from 2001 to 2006 I took UC Berkeley and UC Santa Cruz university extension courses completely covering Bruce Alberts' "Molecular Biology of the Cell", as well as courses in Proteomics, Immunology, Epigenetics and Embryogeneis. This was done "just for fun", but still, I don't feel ignorant of biology.

My point was that "us physicists" are not just a "headstrong bunch" but are also an almost uniquely curious and well-rounded bunch of people, and any **assumption** that we are ignorant is not likely to be true. As I've mentioned in other comments, everyone who submits an essay in this contest tends to feel that "they've figured it out", yet probably some of us are wrong. I'm glad that you've figured it out.

I won't intrude on Ken's space any more, so you get the last word...

Best,

Edwin Eugene Klingman

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Georgina Parry wrote on Sep. 24, 2012 @ 07:08 GMT
Dear Ken Wharton,

A well written, accessible essay. I found it very interesting.I am not sure of the prevalence of the basic assumption that the universe is a computer. However having chosen that assumption to talk about you do a very good job of clearly communicating your viewpoint.

I do like that your essay is forward thinking and suggesting a potentially useful direction for future research, rather than just pointing out the problems. Good luck in the competition. Regards Georgina.

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Author Ken Wharton replied on Sep. 26, 2012 @ 22:56 GMT
Hi Georgina,

Thank you for your kind comments. As for whether the 'universe as computer' claim is prevalent or not, you're probably right that many physicists would not say that they take such a position. But when pressed, many of those physicists retreat to the question: "But what would it mean for the universe *not* to be a computer?" And being in an NSU-mindset, and not hearing much of an answer from the universe-as-computer proponents, they may conclude that such a claim is basically meaningless.

So I hope that at the very least, my essay draws some lines on which one can have a meaningful debate. Given that there is an objective difference between NSU- and LSU-based models, linking the "universe as computer" to the NSU provides an answer to the above question. (One such non-computer-universe is the LSU, a universe that is some solution to a 4D boundary-value problem.)

The point is that many physicists who wouldn't say "the universe is a computer" still assume the NSU is the right framework to best explain the way things really "work". It's the NSU that's the prevalent assumption (or that's the way I see it, anyway).

Cheers!

Ken

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Eckard Blumschein wrote on Sep. 24, 2012 @ 14:31 GMT
Dear Ken Wharton,

Do not belittle what you called “typical engineering-physics”. I agree that your LSU exactly corresponds to the monist view by Einstein, Hilbert, and present mainstream. You are not questioning the fundamentals; you are trying to defend and extend the philosophy on which spacetime and time symmetries arose. I see my essay a challenge to you because it clearly distinguishes between past and future.

You seem already to be not very precise when you wrote in the abstract “predict the future from what we know about the present” but then “predict the future from the past”. This would mean the past is what we know about the present. Noticing your obvious (in words like “we know” and “predict”) anthropocentric point of view, I prefer a notion of objective reality that I described in my essay.

You denied to be a superdeterminist and declared to agree with an unknown to me Huw Price on the issue. Could you please explain his and your position?

Let me out myself as a fan of Karl Popper: I see it justified assuming potentially infinite influences, no matter whether the world is actually open in the sense of potentially infinite or there is objectively no chance to have a complete and trustworthy mathematical description of it.

Do not mistake this as support for Roger Schlafly’s certainly also welcome in fqxi almost nihilistic attitude. I am the optimist who hopes for revelations of foundational mistakes. Maybe, my Figure 5 can be refuted. So far it seems to refute a basic assumption that led to Einstein’s work.

Sincerely,

Eckard Blumschein

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Eckard Blumschein replied on Sep. 25, 2012 @ 07:44 GMT
Dear Ken Wharton,

Ian Durham wrote: "we may all view slightly different realities". My notion of reality is different, and I guess you are also believing in just one objective reality.

You did not respond to my curiosity concerning superdeterminism and Huw Price. Perhaps these are not important. I am not really interested in questions like ultrafinitism.

I would rather appreciate at least one serious argument against my contrary to your position reasoning which I tried to make immediately obvious in my Figures.

Just off topic: In Germany police and intelligence failed for many years to get aware of a NSU (national socialist underground] who murdered. They were misled by a mysterious female DNA that did not belong to the criminals. It happens that mysterious things have a simple explanation.

Sincerely,

Eckard

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Eckard Blumschein replied on Sep. 26, 2012 @ 04:26 GMT
Dear Ken Wharton,

Hector Zenil finds it difficult to reject in the light of your own arguments that the universe is a quantum computer. May I see him right in so far that this conjecture cannot be experimentally falsified before there are quantum computers available that work as envisioned?

Eckard Blumschein

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Author Ken Wharton replied on Sep. 26, 2012 @ 23:50 GMT
Hi Eckard,

Thanks for your comments. While we certainly do disagree on the role of time-symmetry, I don't think our disagreements are *quite* as profound as you made it sound. I'm also interested in describing one objective reality, and I also think we have accidently blundered into foundational mistakes. (Although, granted, we disagree on which mistakes those are...)

If you're pursuing time-asymmetric interpretations then it would probably be time-well-spent to read Huw Price's book, "Time's Arrow and Archimedes' Point". Price lays out in a clearly accessible manner the key issues on this topic, and lays out concrete challenges that anyone pursuing your approach should directly address. His discussion of superdeterminism in that book is what I had in mind in that earlier post, although you can find a summary of the point on this recent profile piece. In a nutshell, merely postulating correlations between a future choice F and a past hidden variable P doesn't require there to be a common-cause in the past of both F and P if one instead entertains straight retrocausal influences from F to P. In this way, the choice at F can still be "free", in every meaningful sense of the word.

Also, we don't have to wait to build a quantum computer to address the question of whether the universe is an NSU-style quantum computer. In fact, I don't see any new insights that would come out of actually having such a computer; see my response to James Lee Hoover above.

I hope to get to your essay at some point, and if I have any comments that I think you might find useful, I'll post them on your essay thread.

Best,

Ken

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Hoang cao Hai wrote on Sep. 27, 2012 @ 04:47 GMT
Dear professor Ken Wharton

"It is these models, the balance of the evidence

suggests, that have a chance of representing how

our universe really works. Not as we humans solve

problems, not as a computer, but as something far

grander." - It seems professor concluded that:

our universe as something far grander ?

Kind Regards !

Hải.Caohoàng of THE INCORRECT ASSUMPTIONS AND A CORRECT THEORY

August 23, 2012 - 11:51 GMT on this essay contest.

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Anonymous wrote on Sep. 28, 2012 @ 17:36 GMT
Ken Wharton,

Congratulations, your excellent essay is in the top 35 essays of this contest.

In spite of the excellent write up in your essay, its title remains highly misleading. When you say, 'Universe is not a computer', it implies as if some physicists actually believe that Universe is a computer, or a machine or an engine etc. etc.

However, most physicists know that the state of the Universe undergoes causal evolution through dynamic interactions among its constituent particles and fields. We humans, in our quest for grasping the physical phenomena, have developed various mathematical models to represent this causal evolution of physical phenomena. The computations which you are attributing to the Universe are essentially the operative parts of our mathematical models and not of the Universe. When you say that Universe is not a computer, you are actually implying that your current mathematical models, representing physical reality, are incapable of computing causal evolution of ALL types of physical phenomena. This inability refers to the weakness of your current mathematical models and not to the Universe itself.

In the light of above clarifications, you are requested to kindly summarize in a few sentences, which of our 'Basic Physical Assumptions' are wrong in your opinion?

Anonymous

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Author Ken Wharton replied on Sep. 29, 2012 @ 19:42 GMT
Dear Anonymous,

I do recognize that the phrase "the universe is a computer" will be interpreted differently by different people, and I agree that this makes the title somewhat imprecise (when taken on its own). But hopefully it is not *too* misleading; some physicists, at least, interpret this phrase as I'm defining it in the essay abstract and body (using the more-precise concept of the "NSU").

So, to answer your question, the incorrect Basic Physical Assumption is that the fundamental "rules" that govern our universe are "computer-like", in that they causally evolve an initial "input state" to generate future states. Because of this assumption, we physicists tend to only look at mathematical models that work in the same manner -- aka the Newtonian Schema.

Hand-in-hand with this assumption is another, more subtle one: The notion that the non-NSU, Lagrangian-style approach is not a valid Schema in its own right, at least when it comes to looking for a fundamental explanation of the evident correlations across space and time. Without giving up this second assumption, it's hard to give up the first.

All the Best,

Ken

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Sergey G Fedosin wrote on Oct. 4, 2012 @ 06:20 GMT
If you do not understand why your rating dropped down. As I found ratings in the contest are calculated in the next way. Suppose your rating is
and
was the quantity of people which gave you ratings. Then you have
of points. After it anyone give you
of points so you have
of points and
is the common quantity of the people which gave you ratings. At the same time you will have
of points. From here, if you want to be R2 > R1 there must be:
or
or
In other words if you want to increase rating of anyone you must give him more points
then the participant`s rating
was at the moment you rated him. From here it is seen that in the contest are special rules for ratings. And from here there are misunderstanding of some participants what is happened with their ratings. Moreover since community ratings are hided some participants do not sure how increase ratings of others and gives them maximum 10 points. But in the case the scale from 1 to 10 of points do not work, and some essays are overestimated and some essays are drop down. In my opinion it is a bad problem with this Contest rating process. I hope the FQXI community will change the rating process.

Sergey Fedosin

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Dean L Waters wrote on Oct. 5, 2012 @ 16:56 GMT
Ken,

Your essay, and your clear framing of the NSU and LSU was the intellectual equivalent of getting hit with a Taser. Coming from having spent years building a Schrodinger-based conceptual framework, I went into a kind of mental paralysis after reading your essay.

I've long intuited that least-action must be one of the most fundamental aspects of Nature, with *something* akin to...

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Author Ken Wharton replied on Oct. 9, 2012 @ 22:11 GMT
Dean,

Thank you very much for telling me about your interesting reaction to my essay; I was quite pleased to hear about it! Getting into a true LSU-mindset is not easy, even for physicists who work with Lagrangians every day. So I'm not at all concerned that you're not sold on the LSU ; the goal of my essay was primarily to raise awareness about the NSU/LSU distinction, and it sounds like...

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Janko Kokosar wrote on Oct. 5, 2012 @ 18:14 GMT
Dear Ken

It is easy to follows derivations, where we use energy, Hamiltonians and so on, because we can imagine energy, momentum etc. But when I try to follow derivation with Lagrangian, I do not know what to imagine - it is some type of energy, but what type. Feynman's book "QED: The Strange Theory of Light and Matter" gives some imagination about for optimization of Lagrangian. You also gave same useful examples. I hope for someone who will clarify Lagrangians as much as possible.

What I think as imagination of derivations in physics, you can see in my article.

In my essay I speculate about importance of principle of uncertainty. I claim that the simplest derivation of it shows, that this principle is more fundamental than wave functions. I claim that wave functions in quantum gravity are not important. Do you have any idea with Lagrangian, how to more simply derive uncertainty principle and how to use it further? Do you know Cramer's interpretation of quantum mechanics? It also shows that "future" influences on past. (A photon do a handshaking and then flies, it is a comparision of all path.) Such approach is also used by Mark Hadley's theory about gravitational explanation of quantum mechanics. Namely, they do not need simple "input-output schema" from past to future.

Best regards Janko Kokosar

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Author Ken Wharton replied on Oct. 9, 2012 @ 22:38 GMT
Janko,

Great question! Yes, when thinking in terms of the LSU, it would certainly be useful to be able to mentally picture Lagrangian densities. But fair warning: the goal is not to translate them back into NSU-style quantities, the goal is to imagine them as fundamental in their own right. So don't go hunting for dynamic entities to use as an analog.

My main advice here is to focus on the fields that make up the Lagrangian, not the Lagrangian itself. Those fields are much easier to picture, although for the LSU it's crucial you think of them as 4D fields spanning space and time, not the NSU version of 3D fields that obey some dynamic equations. Still, in some limit, these two versions yield approximately the same result.

The uncertainty principle looks quite natural from an LSU perspective, as I outlined in this essay. As far as "deriving" the HUP... well, you need to derive it *from* something, and that something is still under-development. But I do see how to use it further; for details look into reference [7].

Cramer's Transactional Interpretation was my first exposure to retrocausal solutions to quantum problems, and has certainly been influential in my thinking on the topic. But I don't think it exactly falls in the LSU camp, and still has quite a bit of NSU-style thinking built into it. (Not to mention that it fails for multiple particles.) I think Mark Hadley is more on the right track.

Best,

Ken

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Cristinel Stoica wrote on Oct. 5, 2012 @ 18:46 GMT
Dear Ken,

The Lagrangian schema has some advantages over the Newtonian schema, or in general over the dynamical system schema. Your essay pointed out this very well, with important insights in the problems of quantum mechanics. I can see how well this relates to your previous essays. My own view on quantum mechanics is again, in my opinion, close to yours (as in the essays on the nature of time). But instead of Newtonian vs. Lagrangian, I identify the problem as local vs. global (please see these slides of a talk I will give in few days, "Global and local aspects of causality").

The importance of the Lagrangian view is related also with the problem of singularities in general relativity, which is in fact the subject of my essay. As you know, the action principle is given by the Lagrangian density



There are singularities for which this Lagrangian density remains smooth or even analytic. It is customary to consider only R, and view the square root of the metric as auxiliary. In fact, from geometric viewpoint, the natural quantity should contain it too, since we don't integrate scalars, but densities or 4-forms. For such singularities R may be divergent, but metric's determinant vanishes and compensates this. This allows the writing of a densitized version of Einstein's equation, whose terms remain smooth at singularities. I explain this in my essay, "Did God Divide by Zero?", and references therein. So we can see that the Lagrangian view is superior in GR too, at least in the case of singularities.

Best wishes,

Cristi Stoica

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Author Ken Wharton replied on Oct. 9, 2012 @ 22:45 GMT
Hello Cristi,

Thanks for the slides and the interesting point about singularities! I found both quite interesting. Yes, we're almost coming from the same perspective; have you tried extending your quantum ideas to multi-particle problems? I find that one can sweep a lot of the "weirdness" under the rug if one only deals with single-particle situations.

As far as the singularities go, I'm still concerned that the fields themselves diverge, even if the Lagrangian density doesn't. I'll have to study your essay and papers and see exactly how it works, but you're right: this might be a nice selling-point for the LSU.

All the best,

Ken

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Cristi replied on Oct. 22, 2012 @ 04:42 GMT
Hi Ken,

Thank you for watching my slides. I'm back now. You asked:

"have you tried extending your quantum ideas to multi-particle problems?"

I did not use the hypothesis that there is only one particle. The sheaf approach works with multi-particle problems too. And the entanglement examples are about two particles.

"I'm still concerned that the fields themselves diverge, even if the Lagrangian density doesn't. I'll have to study your essay and papers and see exactly how it works"

I was concerned about this too. By using appropriate fields, you can rewrite the equations. The resulting equations are equivalent to the usual ones, but in addition remain smooth at singularities, but I'll let you see for yourself.

Best regards,

Cristi Stoica

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Jin He wrote on Oct. 5, 2012 @ 19:19 GMT
MAX PLANK:

An important scientific innovation rarely makes its way by gradually winning over and converting its opponents; it rarely happens that Saul becomes Paul. What does happen is that its opponents gradually die out and that the growing generation is familiarized with the idea from the beginning.

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Dean L Waters wrote on Oct. 6, 2012 @ 03:58 GMT
Last comment. Janko Kolkata mentioned, Feynman's book "QED: The Strange Theory of Light and Matter". If you haven't read this particular version of Feynman's work, I recommend it. There is something about him taking the arguments for the vernacular that adds a slightly different, non-standard perspective on that is missed in some summaries of his work.

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Concerned Public wrote on Oct. 6, 2012 @ 09:45 GMT
Sergey G Fedosin is bombing entrants' boards with the same "why your rating has dropped" message. They are all dated Oct. 4... same message.

WTH? I've seen one fine essay drop 89 (eighty-nine) positions, in "Community Rating" in the past 24 hours, and “Sergey’s note” came BEFORE it plummeted. Hmm.

The vote/scaling of this contest is quite nebulous.

"Hackers Rule!", I suppose!

Well??? What else is one to think? The General Public is... Watching…

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Anthony DiCarlo wrote on Oct. 10, 2012 @ 14:16 GMT
Ken,

I enjoyed your essay but have one question. You stated:

"But it also wasn't easy to fight other anthropocentric tendencies, and

yet the Earth isn't the center of the universe, our sun is just one of many, there is no preferred frame of reference."

When you make a measure of anything at all, "you" DO pick a preferred frame of reference - "you" have to! Therefore, your act of measure imposes BOTH the current boundaries and those that "you" will set in the future. YOU pick the boundaries... and so does every form of life that measures. I see no way out of this apparent fact that a Lagrangian approach would "not" appear to resolve? This fact is why my essay builds a physical model surrounding the physical information that life accumulates (and has past accumulated and sorted out) to makes the current measure ... a measure by a living creature provides the information, and, since we all have our own views regarding the actual measure we must admit that we all possess a different view on what was actually measured. It is only by correlating all of our measures (of the 4D universe that provides all the physical measures) that we can find our common information threads....

Regards,

Tony DiCarlo

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Jayakar Johnson Joseph wrote on Oct. 14, 2012 @ 07:56 GMT
Dear Ken Wharton,

Nature of time in performing finite sets of arithmetic or logical operations with a device differs from the nature of time in that time emerges with the dynamics of the matters of infinite universe.

Though the Tetrahedral-brane scenario and the holarchy of universe described in Coherently-cyclic cluster-matter paradigm of universe, quantizes the universe at its present state; the infinite eigen-rotational cycles of universe describes it in infinity that is not representational as quantum computer, in that string-matter continuum is descriptive for the eternity of the universe.

In this paradigm, as the Lagrangian of a tetrahedral-brane in a holon is relativistic with the other tetrahedral-branes of that holon, computability of its constructs is limited within the holarchy of a holon. Thus for an observer, only the observable universe may be expressional as a computer of the present and not for the future or past, as the nature of time described in this paradigm differs. Thus the present universe does not compute for future and the future is spontaneous, in that variability of chemical potentials in localities has vital role in determining the future states of the universe.

With best wishes

Jayakar

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Sridattadev wrote on Oct. 29, 2012 @ 19:57 GMT
Dear Ken,

Please see the absolute truth of zero = i = infinity . Current limitation of our computers is the unhandled exception of divide by zero, which in fact is the normalcy in the universe. So to your point universe is not like our conventional computers as of date, may be when humans have mastered quantum computing by unleashing the power of divide by zero will the human race fully understand the true nature of the universe.

Love,

Sridattadev.

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Eckard Blumschein wrote on Oct. 30, 2012 @ 18:55 GMT
Ken,

The contest did not solve the problem. I don't refer to FQXi4, also not to the friends of the "as if" in 1925 but to the question put in 1784 by by Lagrange who was the successor of Euler at the Academia in Berlin: (my truncating translation): Mathematics is using infinitely large and infinitely small quantities which are considered self-contradictory by some experts. The Academia asks for an explanation how so many correct Saetze can be derived from a contradictory assumption. It desires a principle that can substitute infinity in a clear and concise mathematical manner.

It is well known that Lagrange did not accept Fourier's harmonic analysis. Can we suspect that the line of reasoning by Lagrange, Hamilton, Hilbert, ..., Feynman, and you suffers from a missing insight? I largely agree with Robert McEachern: "Do not confuse mathematics for physics".

We are doomed to see the world an open system that evades complete mathematical description.

Eckard

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Eckard Blumschein replied on Nov. 10, 2012 @ 08:55 GMT
Ken,

Having put your point of view in question I am still hoping for your defense. After the number of post remained at 138 for quite a while, it even dropped to 137. Since there is little spam, it would perhaps be better if deleted posts were nonetheless counted. This post is #138 again. That number might not necessarily signal to you that something has changed, given you did not cause the deletion of an inappropriate post yourself.

Eckard

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ttch wrote on Nov. 10, 2012 @ 22:40 GMT
Prof. Wharton:

You write that the universe began in a special state of low-entropy order. Victor Stenger (U. of Hawaii) instead argues that the universe began in a state of maximum entropy and its subsequent expansion has enabled its entropy to continually increase. See, e.g., "The Universe: the ultimate free lunch", Eur. J. Phys. 11 (1990) 236-243, available here.

I'm a layman so I don't know how accepted his view is.

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