A Universe Programmed with Strings of Qubits by Philip Gibbs

" ... and reverse engineer the program that codes our universe."

A couple of questions:

(1.) What's the basis for assuming that the computation analogy is valid in this context? Does the fact that we think in terms of "programming" mandatorily mean the Universe does?

(2.) NP-Completeness. This is an issue for quantum computation just as much as it is for classical. Could the proposed reverse engineering even be conceivable unless P=NP? Does it?

Phil, if you just shrug your shoulders about the existence or non existence of SUSY partners, you are not doing physics. You have to decide.

As I've said on vixra log I am quite optimistic about SUSY to be found at the LHC in some form, but it is far from certain. It would not directly affect any work I have done if it was not there.

nikman, there is certainly not anything mandatory about the proposal that the world works like a computer. It is just a hypothesis that we can follow in our pursuit of better understanding. A statement like "the universe is a quantum computer" is currently just a motivational buzzphrase. It does not mean a great deal until we can find a concrete mathematical theory for which it is a reasonable interpretation. It may lead to the development of such a theory.

The justification for considering it is certainly not that we think in such terms. Usually that is not a good guide. The justification is that the mathematics of information and especially quantum information comes up in string theory.

It is not obvious whether or not an answer to the problem P=NP would have any implication for physics. Perhaps if we had a better idea of how the computer "analogy" is realised it would be possible to say more about it.

I like it!

So are you doing an essay this time round?

Oh yeah I should have put page numbers, but you can see them in acrobat reader.

Yes, some people want physics to be purely geometric. prefer it to be purely algebraic.

I don't find any of the other examples you give as convincing. Obviously not everyone is persuaded by these mathematical arguments, we don't all follow the same ideas.

I don't expect any effect of black holes or holography to show up at currently accessible energy scales.

Dear Phil,

Your essay is interesting, and your comments even more so. You clearly state that the paper is speculative, and your comments are very open minded.

You state above that "If physics beyond some scale is something else then the existence of all these remarkable theories is just a crazy coincidence that has led us all astray. I think there is too big a set of coincidences for this to be likely."

In my paper I remark that "potentials derive from 'point particles' and from the fact that scattering data fixes the strength and range of the nucleon potential, but not its shape. As a result:

The Lagrangian formulation provides a convenient technique for inventing new types of fields and investigating their properties.

The mathematical invention of fields offers no guarantee the fields physically exist. But it does allow the invention of Higgs, axions, dilatons, inflatons, anyons, instantons, WIMPs , sphalerons, gluons, and SUSY particles. None of these have ever been seen.

Because academic physics employs this Lagrangian approach to invent new 'fields', it is not really surprising that "all these remarkable theories" end up looking the same. It's less coincidence than a foregone conclusion. And the common characteristic seems to be that all address a relatively minute problem and ignore most of the rest of the universe. For a different approach that addresses current problems of physics I invite you read my essay. In particular, I invite your attention to a very specific set of problems I list that seem to offer a 'testing ground' for any theory of particle physics.

I also commented that a Phys Rev Lett paper I received yesterday implies that the C-field is responsible for recent measurements that show a difference from general relativity predictions. By submitting early, I missed the opportunity to incorporate this info in my essay, but it is relevant.

Thanks for your fascinating comments here.

Edwin Eugene Klingman

Phil,

With all due respect, I am confused by your arguments. Your reply reads:

"I don't find any of the other examples you give as convincing. Obviously not everyone is persuaded by these mathematical arguments, we don't all follow the same ideas."

Are you implying that beauty and logical completeness of a mathematical theory ought to be enough to secure validity of that theory and replace experimental falsification?

"I don't expect any effect of black holes or holography to show up at currently accessible energy scales."

But if this is the case and holography is out of reach, how can one be convinced that AdS/CFT makes contact to reality?

We might wonder whether gravity is at all completely quantized at all. I think that gravitation is actually an emergent effect. More to the point the near horizon condition of an AdS_4 decomposes into AdS_2xS^2. The AdS_2 is the geometry for the sine-Gordon equation, or soliton wave, which is S-dual to a fermionic theory. So I suspect that spacetime is largely a classical field, with quantization at the tree level or O(ħ). Of course Feynman pointed out that general relativity at this level is formally the same as the classical theory! The quantum mechanics behind gravity exists on an other "substratum."

Cheers LC

To the extent that our many confusions and impasses devolve from limitations of the human mind, if P=NP the implications for physics would be beyond anyone's imagination. Mathematical creativity could in theory be automated. Almost all questions that might be asked could be answered. We'd even have a step-by-step quantified physical model for protein folding (surely next to nothing in the great cosmological scheme of things) instead of probabilistic diagrams per statistical physics. The Theory of Everything might be within our reach. What's not to reverse engineer? As Scott Aaronson puts it: "We would be almost like gods."

Or as Frank Wilczek replied when asked what yes-or-no question he'd ask a super-intelligent alien if he were allowed only one: "P versus NP. That basically contains all the other questions, doesn't it?"

If P doesn't equal NP a lot of bets could be off. This is independent of the issue of whether or not the universe computes in any meaningful sense. Is computation itself -- classical, quantum -- robust enough to compress and make comprehensible the fundamental information we hope is out there?

"...If it is because mathematical logic or experiment confirms that they are right, then that's fine. If it is just because we have grown used to the formalism then we need to question if it is the right way to go forward..."

True, Philip, but the trouble is that we have become so clever at mathematics it is possible to frame experimental results in many different ways that seem to point in contrary directions. That is when the second part of your sentence kicks in..the formalism we have been educated in blinds us to other views that may be equally valid but not as 'fashionable'. I am far from being an expert but wonder if theories get shot down for contradicting some minor tenet of a rival theory, and not for contradicting its own premises or experimental results?

Sorry this is off-subject, but it is unfortunate the that name of the black-hole related "holographic principle" has sort of upstaged another possible holographic principle. Holograms have a unique property that if you cut a small portion of the film it will encapsulate the larger picture but at lower resolution. As in fractals, and sort of like how nature seems to work- the universe in a grain of sand sort of thing!

Ervin, I don't think it "ought" to come out that way, but I think it might. Do you think it couldn't?

The AdS/CFT correspondence only works for supersymmetric theory. For non-supersymmetric QCD it may be an approximation but I doubt it would lead to anything other than qualitative results.

Verifying the holographic principle by direct observation may never be possible, just as we may never be able to detect Hawking radiation from a black hole. These things might be forever theories which are necessary to accept for consistency. I am not saying this has to be the case. There are other ways things could pan out.

"I am far from being an expert but wonder if theories get shot down for contradicting some minor tenet of a rival theory, and not for contradicting its own premises or experimental results?"

Yes, this happens. New ideas are sometimes hard to accept because they contradict an old dogma. My series of blog posts about "crackpots" who were right provided a number of historical examples. However, these cases are rare, usually the expert consensus is right, but not always.

The general thinking is that above the symmetry recovery energy, where the Higgs condensate produces particles, physics should exhibit conformal scaling up to the string length. So in a nutshell the physics we observe at the 10 TeV range should then be generically similar to physics up to the string length scale. Further, since the amplitudes scale logarithmically with the energy |A|^2 = probability ~ g^2/4πlog(Λ/E), for Λ = cutoff in scale ~ string tension, the departures at our modest LHC energy are not terribly significant from much higher energy.

Of course nature could pull little tricks on us, where things radically change at some energy between E_s and E_{LHC}. It is my hope that further into this century we become good enough at cosmic ray physics to look at least approximately at 10^3TeV energy particle physics. Yet still nature could have some unobservable change at the 10^{10}TeV scale or so. In that case we are fooling ourselves. Yet if that happens though there might be some signatures of this at the energy scale we can probe.

In this way we may get indirect measurements of physics involving the holographic principle and Hawking radiation. The recent observation of the fluid-like properties of quark-gluon plasmas is being investigated as a "soft black hole" physics of Hawking radiation. It could also provide signatures for how gluon chains are equivalent to the graviton.

The one sad fact of life is that our power to measure and observe nature at these most extreme scales is rather indirect or "oblique." Lawrence Krauss mentioned something similar to this last year or back in 2008 with the lament that this could sign the ultimate end to the foundations of physics or cosmology. Yet, there is plenty of wiggle room to work within for now. Not only that, science is not so much about coming to know everything, but knowing about something relatively well.

Cheers LC

In 2006, I predicted the perfect fluid based on my C-field theory. It is beyond me why most physicists would rather speculate on unseen entities based on unreal mathematics instead of examining real fields with real Yang-Mills non-linearities that account for most of the real mysteries of current physics, while not requiring any new particles. I suspect it has to do with both education/brainwashing and with the remark made below that "[one] wonders if theories get shot down for contradicting some minor tenet of a rival theory, and not for contradicting its own premises or experimental results?"

I am also puzzled that so many focus on speculative physics while literally ignoring known facts that are clearly telling us real non-speculative physics. There is clearly as much psychology as physics at play here.

As for science being "not so much about coming to know everything, but knowing about something relatively well" that may be a technologist's perspective but it is certainly not that of all physicists.

Edwin Eugene Klingman

Phil "...the expert consensus is right, but not always"

A consensus could be very wrong - vide a whole gamut of ideas from the phlogiston to you name it . And what about now - is there an expert consensus? From all that I gathers physics is like the Tower of Babel, people talking in different language. Nature cannot be that multilingual, I think it acts in a simple direct way - like your qubits for example.

The geometry and the algebras are purely linked in the sphere.

Steve

Excellent paper, a work of science and not science fiction. It is nice to read a paper written by someone with a full grasp of current theory that is intended for a general audience and is sufficiently technical to justify its statements, but not so technical as to lose its dramatic story.

My question is whether you think one could see the appearance of effects analogous to gravity for quantum computers with 4N qubits?