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What If Time Really Exists? (2008)

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161–170 of 215 posts

Re: What If Time Really Exists? (2008)

#161

Earlier quoted context omitted.

> In a classical word, you must simulate only one path. In a quantum word, you must simulate both. You don´t need some magical conscious observer to force the collapse of the wave function. A CCD detector of a camera or a simple wall is enough to force that the "wave" collapse into a "particle" and the detector or wall gets a small spot where the "particle" hits it. While the alternative seems a little too far out to…

It often seems to me that Godel's incompleteness is the same phenomenon as Heisenberg's uncertainty, just in different domains.

https://arxiv.org/abs/quant-ph/0402197

>In 1927 Heisenberg discovered that the ``more precisely the position is determined, the less precisely the momentum is known in this instant, and vice versa''. Four years later G\"odel showed that a finitely specified, consistent formal system which is large enough to include arithmetic is incomplete. As both results express some kind of impossibility it is natural to ask whether there is any relation between them, and, indeed, this question has been repeatedly asked for a long time. The main interest seems to have been in possible implications of incompleteness to physics. In this note we will take interest in the {\it converse} implication and will offer a positive answer to the question: Does uncertainty imply incompleteness? We will show that algorithmic randomness is equivalent to a ``formal uncertainty principle'' which implies Chaitin's information-theoretic incompleteness. We also show that the derived uncertainty relation, for many computers, is physical. In fact, the formal uncertainty principle applies to {\it all} systems governed by the wave equation, not just quantum waves. This fact supports the conjecture that uncertainty implies randomness not only in mathematics, but also in physics.

Re: What If Time Really Exists? (2008)

#162
post #16

Earlier quoted context omitted.

The appearance that quantum effects might be attributed to 'hacks' probably has more to do with the hackish nature of the Copenhagen interpretation. For instance, there is no stated physical explanation for the collapse of a wavefunction--it is only an extremely convenient way of explaining many experiments. A crude analogy--you can describe the flipping of coins with simple probability, but this is a non-physical ye…

What do you think of Bohm's interpretation ?

Bohm's interpretation is just many worlds with a "world particle" tacked on. That particle doesn't affect anything and it's only purpose is to get rid of those pesky other worlds.

Not only is it superfluous structure it makes the theory non-local, which is hard to reconcile with relativity.

If you have no a priori reason to reject a multiverse Bohm's theory is quite uninteresting.

Re: What If Time Really Exists? (2008)

#163

Those who say we live in simulation, are they saying that there is a creator(s)?

Yes. Except that we're probably not their chosen people, just one of the experiments.

One of my pet hypotheses is that the universe is so vast, that god doesn't have the slightest clue that we're here.

Re: What If Time Really Exists? (2008)

#165

Between modern physics suggesting time and space may be illusions, leading technologists agreeing that we're almost certainly in a simulated reality, and many ancient traditions being certain that this is all an illusion, I may have to have to go ahead and take this seriously....

>leading technologists agreeing that we're almost certainly in a simulated reality Just to elaborate, this is really easy to show. Just take two pieces of paper, and scribble all over one of them for 10-15 minutes. Then crumple them up and throw them to the ground. The blank one will fall to the ground smoothly. But the one that has a lot of image information will tax the Universe's GPU, because it isn't able to comp…

For anyone who didn't get it, the first half of my comment was sarcasm.

"leading technologists agree that we're almost certainly in a simulated reality" is false.

Re: What If Time Really Exists? (2008)

#166

Earlier quoted context omitted.

> In a classical word, you must simulate only one path. In a quantum word, you must simulate both. You don´t need some magical conscious observer to force the collapse of the wave function. A CCD detector of a camera or a simple wall is enough to force that the "wave" collapse into a "particle" and the detector or wall gets a small spot where the "particle" hits it. While the alternative seems a little too far out to…

It often seems to me that Godel's incompleteness is the same phenomenon as Heisenberg's uncertainty, just in different domains.

Absolutely not. The uncertainty in Heisenberg's uncertainty principle stems from the fact that you can not have a signal simultaneously well localized in both time and frequency. If you want a signal that is very well localized in time, then you need a short signal, a single spike. But the frequency of a single spike is not well defined, if you want a signal with a well defined frequency, you need something like a sine wave. And to make the frequency of a sine wave well defined, you need a long piece of it which of course means that the signal is no longer well localized in time. That is the heart of Heisenberg's uncertainty principle, you can not have signals that are simultaneously well localized in time and frequency.

Gödel's incompleteness theorems have in some sense much deeper reasons, they are based on the logical consistency of the entire construction. Maybe you can look at it in a similar way, a theory is an object like a signal above and the properties of being consistent and complete can not be realized at the same time. But I have a hard time imagining that this could really be similar to signals where you can trade localization in time for localization in frequency and vice versa, but how would you trade a bit of consistency for a bit of completeness?

EDIT: To be a bit more concrete, in classical mechanics you have to specify position and momentum (velocity) of a particle to specify its state, those are two independent properties that can have specific and independent values. That is not true in quantum mechanics, there position or momentum alone fully specify the state of the system. The wave function (in position space) tells you where the particle is with what probability, the frequencies of the wave function tell you what the momenta are with what probability.

And from here it is the same as above, if you force a particle into a very well localized position, i.e. make the wave function a narrow spike at some place, then the frequencies and therefore the momenta are no longer well defined. If, on the other hand, you make the wave function of the particle like a sine wave, then you get a well defined frequency and therefore momentum but the wave function becomes spread out across space and the position is therefore no longer well localized.

Re: What If Time Really Exists? (2008)

#167
post #154

Earlier quoted context omitted.

I wouldn't be so sure about that. Max Planck himself said: "A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it." [1] [1] - https://en.wikiquote.org/wiki/Max_Planck

Science isn't a religion but scientists can be zealots. The scientific principle is the antithesis of religion but scientists can be irrational like any other human. The good thing about the modern era is that even when institutional biases may momentarily prevent a theory from gaining mainstream recognition at least it will be preserved as part of the body of scientific knowledge so future generations can rediscover…

> Science isn't a religion

Science might not be, but there are plenty of Scientismists out there.

Re: What If Time Really Exists? (2008)

#168

Earlier quoted context omitted.

The simulation argument comes from the fact that there a quite a lot of physics effects that are both surprising, and look an awful lot like dirty hacks that a programmer might put it. Quantum physics looks a lot like lazy evaluation (State doesn't exist until "observed"). The speed of light seems like a hack to prevent an n squared problem of everything in the universe effecting everything at the same time.

> Quantum physics looks a lot like lazy evaluation (State doesn't exist until "observed"). This is a common misconception (¿among programmers?). Let's think about the double slit experiment. https://en.wikipedia.org/wiki/Double-slit_experiment In a classical word, you must simulate only one path. In a quantum word, you must simulate both. You don´t need some magical conscious observer to force the collapse of the wav…

> In a classical word, you must simulate only one path. In a quantum word, you must simulate both. You don´t need some magical conscious observer to force the collapse of the wave function. A CCD detector of a camera or a simple wall is enough to force that the "wave" collapse into a "particle" and the detector or wall gets a small spot where the "particle" hits it.

This is a common misconception (among programmers). There's zero experimental evidence for the effect you mention, and zero theoretical derivation. Circumstances under which wave function collapses is the greatest mystery of QM.

Re: What If Time Really Exists? (2008)

#169

Earlier quoted context omitted.

The simulation argument comes from the fact that there a quite a lot of physics effects that are both surprising, and look an awful lot like dirty hacks that a programmer might put it. Quantum physics looks a lot like lazy evaluation (State doesn't exist until "observed"). The speed of light seems like a hack to prevent an n squared problem of everything in the universe effecting everything at the same time.

> Quantum physics looks a lot like lazy evaluation (State doesn't exist until "observed"). This is a common misconception (¿among programmers?). Let's think about the double slit experiment. https://en.wikipedia.org/wiki/Double-slit_experiment In a classical word, you must simulate only one path. In a quantum word, you must simulate both. You don´t need some magical conscious observer to force the collapse of the wav…

I've been watching a few video series by mathematicians on quantum computers and they're pretty interesting. I wish they could hook up with some animators to make it a little easier to understand.

There's a lot of complex maths and polar notation. There are a couple of good simulators out there that lets you play with qubits and their probabilistic coefficients.

I'll be honest that I was never all that great at the higher maths and a lot of this taxes my brain or goes way above my head. But all these quantum computers are deterministic. The simulators can fully simulate them.

It's just that simulating several qubits requires gigs and gigs of ram. A real quantum computer can't do anything you can't do with a traditional computer, it can just do it in a more computational faster time and fewer resources.

You can run small quantum programs yourself on the IBM cloud quantum platform. They allow people to queue up programs to run, similar to old punch card systems:

http://www.research.ibm.com/quantum/

Re: What If Time Really Exists? (2008)

#170

Between modern physics suggesting time and space may be illusions, leading technologists agreeing that we're almost certainly in a simulated reality, and many ancient traditions being certain that this is all an illusion, I may have to have to go ahead and take this seriously....

The simulation argument comes from the fact that there a quite a lot of physics effects that are both surprising, and look an awful lot like dirty hacks that a programmer might put it. Quantum physics looks a lot like lazy evaluation (State doesn't exist until "observed"). The speed of light seems like a hack to prevent an n squared problem of everything in the universe effecting everything at the same time.

We do not observe states, we observe (measure) "observables"; both exist independently from any observers; while state evolves deterministically, an observable, when measured, takes a value, subject to a probability distribution on a set of values, which depends on both the state and the observable in question. (That's basically QM in a nutshell.)
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