Stephen Wolfram's post about spacetime

[David Neves]

What do you think of Stephen Wolfram's blog post about spacetime?

http://blog.stephenwolfram.com/2015/12/what-is-spacetime-really

 

[.Scott]

I'm okay with him to

But if there’s really going to be a simple model of physics, it seems wrong that such a rigid structure [a Cartesian grid] for space should be burned in, while every other feature of physics just emerges.

. Beyond that, I think he needs to bone up some more on QM before trying to build the universe.

 

[Hornbein]

What do you think of Stephen Wolfram's blog post about spacetime?

http://blog.stephenwolfram.com/2015/12/what-is-spacetime-really

John Conway, the inventor of cellular automata, doesn't care for Wolfram's idea. If it's not good enough for John, it isn't good enough for me.

 

[Jimster41]

John Conway, the inventor of cellular automata, doesn't care for Wolfram's idea. If it's not good enough for John, it isn't good enough for me.

I would be interested in Conway's critique... got a link?

 

[kodama]

i read the linked article Stephen Wolfram is clearly a fan of spin networks spin foam. he thinks some fundamental object like spin networks can give rise to both GR spacetime AND the standard model and QFT. in this he is similar in spirit to Bilson-Thompson ribbons. he even prints Lord Kelvin knot theory of the aether.

ultimately he doesn't think spin networks need to give rise to GR and SM via hamiltonian a la LQG. he thinks there is some set of principles similar to a computer program that give rise to spacetime and QFT. he acknowledges that physics is synonymous with QFT research and he wants to move away QFT for a paradigm similar to a computer program code.

 

[Hornbein]

I would be interested in Conway's critique... got a link?

Conway: I think he is wrong. And I am rather astonished that he has the opinions that he has, because he supposedly studied physics. I shouldn’t say “supposedly”—pardon me. He should be aware of the fact that the universe behaves in a manner that—at least most competent physicists believe— is not deterministic. And cellular automata are things that, like the life game, are deterministic. So in my opinion, it’s provable that the universe is not a cellular automaton.

http://www.ams.org/notices/201305/rnoti-p567.pdf

 

[MacRudi]

The more went into fundamental research the better. So why not? If he has a different view on this theme, then it can be, that we get in time other equivalence principles. It is always good to reflect things from another view.
So if he thinks hamiltonian-dirac-lagrange chainlogic is not proper for his model, then he should find other ways. Why not?

I always appreciate new thinking for same problems. This is research and this is science.

 

[ZapperZ]

The more went into fundamental research the better. So why not? If he has a different view on this theme, then it can be, that we get in time other equivalence principles. It is always good to reflect things from another view.
So if he thinks hamiltonian-dirac-lagrange chainlogic is not proper for his model, then he should find other ways. Why not?

I always appreciate new thinking for same problems. This is research and this is science.

While there certainly should be research on different aspects on the things we are tackling with, I question whether this exact work will have the same type of publicity if it were done by a no-name physicist. In other words, how much of this is due to a cult of personality?

There is also another aspect to this, in which one would ask about Wolfram on "what have you done for me lately?". The last thing he did that garnered quite a bit of publicity was his book "A New Kind of Science". That book was http://jfi.uchicago.edu/~leop/AboutPapers/WolframReview.pdf by one of the Giants in the field, Leo Kadanoff, in Physics Today and it didn't come out unscathed. That book did not create its lofty goal of "a new kind of science".

So the issue here isn't discouraging or dismissing any effort to look at something in a different way, but rather having the attitude, based on his previous efforts, of "I'll believe it when I see it".

Zz.

 

[MacRudi]

While there certainly should be research on different aspects on the things we are tackling with, I question whether this exact work will have the same type of publicity if it were done by a no-name physicist. In other words, how much of this is due to a cult of personality?

There is also another aspect to this, in which one would ask about Wolfram on "what have you done for me lately?". The last thing he did that garnered quite a bit of publicity was his book "A New Kind of Science". That book was http://jfi.uchicago.edu/~leop/AboutPapers/WolframReview.pdf by one of the Giants in the field, Leo Kadanoff, in Physics Today and it didn't come out unscathed. That book did not create its lofty goal of "a new kind of science".

So the issue here isn't discouraging or dismissing any effort to look at something in a different way, but rather having the attitude, based on his previous efforts, of "I'll believe it when I see it".

Zz.

It doesn't really matter if he has a name or if he has no name in community.

If he finds principles and we can ad it to our view with a more widespread view on a problem, then he will earn his fame. For me it is not a problem.
Only because some other people are jealous on other people like it is actually with Ed Witten or it was in the past with Einstein doesn't really matter in the whole history of science. It will turn out in time, what someone is really adding to the science research.

Look at Stringtheory. We have since 30 years a complex research of many physicists and mathematicians who found out a lot of equivalences like T duality, S duality etc and could describe constants (finestructure constant, coupling constant etc) as fieldtheory mathematics and are not constants anymore in our view, we could find a lot of mathematical proof out of stringtheory in axiomatic systems which is now in itself consistent, we had before only as assumptions. This happened out of many research of many no name physicists and mathematicians and some very brillant now with a name as giants in physics and mathematics. This is a completely new view and this is out of research from many people who found it because they were going different paths but showed us that in time they worked all on the same problem. Someone had to put it together.

For me every research is good and even it can happen that it is waste of time. But in the end all will help to find the right theory for everything.
What we learned from Einstein was, that we need different views on a subject and we find equivalence principles and can put it together in a geometry as field theory. This had happened in String theory extremely consistent in itself, which helps every other theory too. We see it in QFT and QCD e.g. Without stringtheory we would talk today about kind of Numerology like Astrology in particle physics (most do it without knowing anything of stringtheory and QFT as before ;-) ). And the more we find from other views that shows us equivalence principles, the better we find the ToE. Science history told us, as long it is all open scource and to review from everyone, then we go further. If we try to behave like the Pythagoreer and hide inconsistants and incommensurrabilities then we will fail and someone like Plato has to come. But this was 100 years later. 100 years are timewasting.

 

[Demystifier]

Conway: I think he is wrong. And I am rather astonished that he has the opinions that he has, because he supposedly studied physics. I shouldn’t say “supposedly”—pardon me. He should be aware of the fact that the universe behaves in a manner that—at least most competent physicists believe— is not deterministic. And cellular automata are things that, like the life game, are deterministic. So in my opinion, it’s provable that the universe is not a cellular automaton.

't Hooft, who is a Nobel Prize laureate, would disagree with you. He thinks that a deterministic cellular automaton lies behind the laws of quantum mechanics.

 

[Hornbein]

't Hooft, who is a Nobel Prize laureate, would disagree with you. He thinks that a deterministic cellular automaton lies behind the laws of quantum mechanics.

Me? I am not John Conway.

 

[Demystifier]

Me? I am not John Conway.

Sorry, I've missed the the fact that you quoted him.

 

[MathematicalPhysicist]

't Hooft, who is a Nobel Prize laureate, would disagree with you. He thinks that a deterministic cellular automaton lies behind the laws of quantum mechanics.

Just because someone won some prizes doesn't mean he's always right. (I think world being determinstic or not is something which will always be unsolved, but that's me unprized poster's opinion).

 

[MathematicalPhysicist]

Well the laws of QM are determinstic, before you measure anything the Schrödinger equation is determinstic and the propagation with the evolution unitary operator is determinstic as well, but when you measure it stops becoming determinstic and probability comes in.

 

[Demystifier]

Just because someone won some prizes doesn't mean he's always right. (I think world being determinstic or not is something which will always be unsolved, but that's me unprized poster's opinion).

Indeed, even the opposite effect may happen: We all have silly ideas occasionally, but someone who is very respectable and famous (due to his/her success in the past) can more easily publish it, and even make others pay attention.

But then again, just because the idea is silly, doesn't mean it's wrong.
Bohr ones said to Pauli: Your idea is crazy, but not crazy enough.

 

[member 11137]

What do you think of Stephen Wolfram's blog post about spacetime?

http://blog.stephenwolfram.com/2015/12/what-is-spacetime-really

Very interesting ideas.

For me (I may be wrong), there is a kind of convergence into that direction in the scientific research. As illustrations for this sensation :
1) "Physicists Discover Geometry Underlying Particle Physics" (2013) http://www.math.columbia.edu/~woit/wordpress/?p=6260
2) The filaments structures in cosmology (see diverse pictures, e.g.: http://cosmicweb.uchicago.edu/filaments.html)

I believe (it's not science I know) that we are accumulating informations at all scales and in diverse branches proving us the existence of some underlying geometrical structure. Well fascinating. And after all the empty regions between two electrons and between the Earth and the Sun should have similar properties, or not?

 

[Vladimir Nachev]

The less resistance you meet traveling in space the faster you travel the faster you travel the slower time gets for you compared to the other objects with higher resistance(gravitational, mass, waves, particles, even light) if you can actually shut off external interactions with a body you can make it stop "aging" in time but it must disappear from vision because it will move away with the speed of light until some force interacts with it or some mass collides with it I mean even if a particle is colliding with a photon it MUST become slower than the photon itself that's why when a photon collides with a magnetic field it slows down like the experiments for slowing down a photon but there should be a qualitive constant that if a photon is distressed too hard with a too slow moving wave it should collapse in some way

 

[A. Neumaier]

just because the idea is silly, doesn't mean it's wrong.

But because an idea is silly, it is very unlikely that it is right. Of 10000 ideas that work out, only 1 or 2 may seem silly at first.

 

[Demystifier]

But because an idea is silly, it is very unlikely that it is right. Of 10000 ideas that work out, only 1 or 2 may seem silly at first.

Yes, but here the relevant question is this: What are the odds that a silly idea is right when it is proposed by a famous expert in the field?

 

[atyy]

't Hooft, who is a Nobel Prize laureate, would disagree with you. He thinks that a deterministic cellular automaton lies behind the laws of quantum mechanics.

Wolfram's model is nonlocal, so it's just vanilla physics, unlike 't Hooft's. Of course, Bell doesn't rule out 't Hooft's superdeterminism, but as far as we can tell, such a model would not be useful for us. If AdS/CFT is correct, and if a lattice model of the CFT is possible, then a Bohmian model of AdS/CFT would be possible, which should have a cellular automata implementation. So the main open questions are whether AdS/CFT is correct, and whether a lattice model of the CFT in question is possible.

Progress on these ideas have come from many others apart from Wolfram in ways much much more substantial than a blog post.

 

[A. Neumaier]

What are the odds that a silly idea is right when it is proposed by a famous expert in the field?

If after a year it is still silly, there is hardly any difference in the odds.

 

[Demystifier]

If after a year it is still silly, there is hardly any difference in the odds.

Even if the silly paper received a lot of citations?

 

[A. Neumaier]

Even if the silly paper received a lot of citations?

Yes. For example, Everett's relative state (MWI) paper has a huge number of citations. People like silly thins if they are well done. The (lack of) scientific content doesn't matter.

 

[friend]

In his article, Stephan Wolfram writes, "you realize that the only thing observers can ever actually observe in the history of the universe is the causal network of what event causes what other event." And he also writes, "as soon as there’s causal invariance, it basically follows that there’ll be Special Relativity on a large scale."

But as soon as you have a conjunction things (e.g. points of space), then you have a causal structure, since

(p Λ q) → [(p → q) Λ (q → p)],

where Λ is logical conjunction and → is logical implication. And there's no escaping the fact that the points of space exist in conjunction since we label each point with different coordinates and observe great regions of space existing at once. And there's no denying that implication is related to causation. For to say that p causes q is to say p therefore q, which is implication. So I certainly agree with the authors perspective.

 

[black hole 123]

't Hooft, who is a Nobel Prize laureate, would disagree with you. He thinks that a deterministic cellular automaton lies behind the laws of quantum mechanics.

if the universe is deterministic then counterfactual definiteness must be wrong, am i correct? so EVERYTHING we do is predetermined, even the outcome of future experiments?

this is like saying a murderer isn't guilty because he was predetermined to do it. i find it hard to believe.

 

[PAllen]

if the universe is deterministic then counterfactual definiteness must be wrong, am i correct? so EVERYTHING we do is predetermined, even the outcome of future experiments?

this is like saying a murderer isn't guilty because he was predetermined to do it. i find it hard to believe.

No, he was pre-determined to be guilty, and others are pre-determined to take compensatory actions (assuming they are pre-determined to catch him).

 

[Demystifier]

if the universe is deterministic then counterfactual definiteness must be wrong, am i correct?

No, determinism is not in contradiction with counterfactual definiteness. If future is determined by initial conditions, counterfactual definiteness is still true in the sense that one can say what the future would be if the initial conditions were different.

so EVERYTHING we do is predetermined, even the outcome of future experiments?

Yes.

this is like saying a murderer isn't guilty because he was predetermined to do it. i find it hard to believe.

This is an ethical problem, not a scientific one.

Scientifically speaking (see also the post above by Pallen), you find it hard to believe it because you were predetermined to find it hard to believe it, not because it is wrong by itself.

 

[atyy]

this is like saying a murderer isn't guilty because he was predetermined to do it. i find it hard to believe.

The alternative is that a murderer isn't guilty because quantum fluctuations made him do it.

 

[Demystifier]

The alternative is that a murderer isn't guilty because quantum fluctuations made him do it.

I wonder if there is any interpretation of QM in which he is really guilty?

 

[ShayanJ]

I wonder if there is any interpretation of QM in which he is really guilty?

Well, if we want to talk only in terms of physics, a murderer isn't guilty because of a murder the same as a lightning isn't guilty of killing the person it hit! They're just two physical processes, why should one be different?