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Entanglement Could Be a Deterministic Phenomenon
KentuckyFC writes "Nobel prize-winning physicist Gerard 't Hooft has joined the likes of computer scientists Stephen Wolfram and Ed Fredkin in claiming that the universe can be accurately modeled by cellular automata. The novel aspect of 't Hooft's model is that it allows quantum mechanics and, in particular, the spooky action at a distance known as entanglement to be deterministic. The idea that quantum mechanics is fundamentally deterministic is known as hidden variable theory but has been widely discounted by physicists because numerous experiments have shown its predictions to be wrong. But 't Hooft says his cellular automaton model is a new class of hidden variable theory that falls outside the remit of previous tests. However, he readily admits that the new model has serious shortcomings — it lacks some of the basic symmetries that our universe enjoys, such as rotational symmetry. However, 't Hooft adds that he is working on modifications that will make the model more realistic (abstract)."
Free will is a sham. Of course, believe whatever you will. It's not like you have a choice.
I've often been skeptical of the idea that you could disproove a hidden variable. The hidden variable itself could be dynamic controlled by another hidden variable.
I guess I just assume that there is more we don't know about the universe that we do know about it.
In his model of the universe, everyone has a beard or goatee.
Bell's inequalities fall apart if current particles can "know" about future measuring devices. However, for particle physics, neither direction of time is privileged. Particles are just as likely to be influenced by future interactions as they are by past interactions. Because of this, there is no "action at a distance". Influences travel along the backwards light cone and remain perfectly relativistic.
This simple, straightforward solution has been largely ignored.
Note that most interpretations of quantum mechanics are explicitly time asymmetric due to the "collapse" caused by observation. Cramer's transactional theory is an exception, it is symmetric and there is no collapse, but it doesn't get much attention.
Come up with a generic theory...And then tweak it to match reality.
I'm afraid people do that all the time, each one new and different.
Uh...yeah. That is how the scientific process is supposed to work. You form a hypothesis based on what you know already, you test it, and as the results of your tests roll in, you modify the hypothesis accordingly. Form and then tweak. This is the essence of all scientific progress we have made to date.
Why do you have a problem with this? I'd say the proof is in the pudding.
But why do they bother? We already have the ultimate "parameterize and tweak the theory to match reality" theory in String Theory, so why bother with anything else?
Because string theory lacks evidence, and we don't have the technological means to gather much evidence for it (at present). Also, at present, the theory fails to offer much utility (we can't build any useful devices based on string theory).
Your attitude sounds a bit scarey. I read it as, "we already KNOW the truth, so why continue looking?" This very attitude inhibited scientific progress for most of human history. I wonder if it also inhibits you?
If Stephen Wolfram turns out to be correct, his ego will collapse into a singularity form the rapid mass inflation it will under go, taking the Earth with him.
Shop smart, Shop S-Mart.
...because I choose to believe that I have free will.
If you don't believe in free will, then there's no use arguing with me, because it's been pre-determined that I will believe in free will.
PS:
Isn't trying to change someone's mind pretty much a futile gesture to a determinist?
Firstly, I find the title of the submission a little odd. I mean, Entanglement can easily be understood as "deterministic" in a sense in conventional quantum mechanics. The generation of entanglement via the Schroedinger equation is quite deterministic. What's usually understood as non-deterministic is what happens when you measure.
I saw a talk by t'Hooft a number of years ago (I actually had lunch with him and my adviser). He was talking about a similar idea then, and my interpretation was that it evaded Bell's Theorem by being a non-local hidden variables theory. I haven't read the paper, so I'm not certain if this new idea is significantly different.
For background: Bell's Theorem is a result that shows that a local realistic hidden variables theory (a theory where each, say, particle has some hidden degree of freedom that determines the outcome of a measurement on it before the measurement is made) cannot reproduce the results of quantum mechanics for an entangled quantum state. To get around this obstacle, it's generally said that you either have to give up determinism (things don't have one specific state, etc. , before they're measured) or locality (the outcome of an experiment in one place may be totally changed by events happening at the same time arbitrarily far away)
"You call it a new way of thinking; I call it regression to ignorance!" -- Operation Ivy
When you model the universe in terms of will-less mechanisms, you will (amazing!) discover that free will is a logical impossibility.
Trying to model free will in terms of physics is like trying to describe the combustion engine using only the words found in a book on home gardening.
The only reason some people find this personally problematic is because they have decided that our current model of physics is also the concrete, accurately-represented holy truth. In fact, our current model is just an abstract representation of something we can't see, and it is just the best we've come up with so far (in fact, any scientist worth his salt will predict that our models will change in the future).
So the quantum-mechanical model of the universe is incompatible with any free-will-is-real model of the universe. So what? This incompatibility doesn't make either theory right or wrong. The evidence for each theory is all that matters.
As Epicurus (one of the fathers of the modern scientific method) advised, "if several theories are consistent with the observed data, retain them all."
Hidden variables in this case should be thought of as a hidden micro-states. A hidden variable theory would have quantum mechanics be something like thermodynamics; i.e., a theory that is not really basic, but appears so as we cannot see the fine scale true reality. Einstein was convinced that this had to be the case.
The tests of Bell's Theorem shows that no locally causal hidden variable theory is viable. This says basically that one of these must be the case
There are no hidden variables (i.e., true quantum uncertainty applies, and quantum mechanics is correct).
The speed of Light can be violated (i.e., there are hidden states that can exchange information faster than the speed of light). This implies, by the way, causality failures would be possible, so that in principle you could do something like kill your grandfather and prevent your own existence.
There is action at a distance (i.e., the theory is non-local).
There has long been a viable theory, that of Bohm, that replicates normal quantum mechanics. It's non-local.
I cannot tell from a read of the article (and without seeing the underlying paper) if 't Hoof has a non-local theory or just how he stays consistent with Bell's Theorem.
Why ascribe the idea's of Konrad Suse to Wolfram?? Calculating space, 1967 (PDF)
Or maybe a Sorceror.
Or maybe a Christian.
Modeling the universe in terms of magic is what humanity has been doing for most of recorded history.
Modeling the universe in terms of mechanical interactions of particles or waves is the new-and-cool. And we are still getting our heads around how to do it.
It doesn't matter what you base a model on, the value of a model is purely a matter of how good it works as a predictive tool (or as an aesthetic object for the artistic). If I model the moon as cheese and it gives the right answer for seismic readings, then it's a good model. If you are looking for absolute truth in a model, then I am afraid you are living in the wrong universe.
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