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Quantum Entanglement Drives the Arrow of Time

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Re: Quantum Entanglement Drives the Arrow of Time

#92

Earlier quoted context omitted.

Doesn't it depend on what it means for a theoretical construct to be "real" or not? Isn't "does it work" a better question?

Don't get confused by simple words such as "real". It means what it obviously mean in everyday life. For instance, apples are real, and gravity is real. So when you drop an apple, what happens? It falls. Now what really, ultimately happens? It falls.

Once in Hawaii, at a meeting of philosophers sitting around a table discussing reality, several days passed and Suzuki said nothing. And finally the chairman said, "You've been silent all this time. Would you say something about reality." And Suzuki didn't say anything. I think he may have looked up. Finally the man said, "Well, is this table real?" And Suzuki said, "Yes." And then the man said, "In what sense is it real?" And Suzuki said, "In every sense."

Re: Quantum Entanglement Drives the Arrow of Time

#93
post #14

I thought it was the second law of thermodynamics that already explained the arrow of time? Well, that and friction?

The second law is an empirical statement. This entanglement based approach is an attempt to understand the underlying physical mechanism that controls the spread of entropy. If this picture is right, the next question is what is the physical process behind entanglement.

The second law was proven as a statistical outcome. Ordered states are vastly outnumbered by disordered ones.

And isn't the whole description of entanglement based on empirical observations anyway?

Re: Quantum Entanglement Drives the Arrow of Time

#94
post #69

I love following article: http://www.flownet.com/ron/QM.pdf It basically shows that observation (measurement) and entanglement are the same things. Think about it: particles are not magically going out of superposition as we observe (measure) them. We (our atoms) become entangled with those particles, we become superposition. It's just propagation of entangled state. Why we don't perceive ourselves as in superpositio…

Superposition is not a one time thing, after entanglement uncertainty shows right back up just within a smaller range.

Re: Quantum Entanglement Drives the Arrow of Time

#97
post #71
post #69

I love following article: http://www.flownet.com/ron/QM.pdf It basically shows that observation (measurement) and entanglement are the same things. Think about it: particles are not magically going out of superposition as we observe (measure) them. We (our atoms) become entangled with those particles, we become superposition. It's just propagation of entangled state. Why we don't perceive ourselves as in superpositio…

I have a question: What does being in a superposition mean exactly here? I only know the term from classical mechanics, e.g. that an acceleration vector in R^3 can be seen as a superposition of three accelerations along the base vectors (a linear combination).

It's kind of like that. The state of a particle in classical mechanics is a linear combination of some basis vectors which are not it's states as such. But the superposition in QM is the superpositions of states. The phase space in classical mechanics is not a vector space, but in QM it is. This is a fundamental difference because in QM you can take any number of states, make a linear combination a it will result in another perfectly valid state. Not so in classical mechanics. For example, consider a particle orbiting a point. If you take some position vectors as it moves and make a linear combination, the resulting vector will not be a possible position of a particle in this system. In QM, it would necessary be another possible state. This is a slightly sloppy example, but I hope you get the gist.

Re: Quantum Entanglement Drives the Arrow of Time

#98

Does it seem to anyone else that quantum entanglement and decoherance is the universes way of doing the least amount of computation possible? Like the universe is lazily loaded?

It's funny, but the Multiverse interpretation seems to suggest the exact opposite - the Multiverse as an exploration of all possible states.

Re: Quantum Entanglement Drives the Arrow of Time

#99
post #88
post #64

This is nonsense; entropy and the arrow of time are essentially a many-body effects and require no quantum effects to occur. A simplest way to see it is to make small simulation of a, say, 1000 gas particles with only classical bouncing in a one side of a box partitioned in half with a barrier, obviously with a time-reversible numerical method -- after the removal of the barrier the gas will evenly spread over the bo…

Here's a crazy thought... the really stonking smart physics PhDs who have spent their whole lives working on this problem are perfectly aware of the classical 18th-century physics you are referencing, and they've found it an unsatisfactory explanation. Perhaps you might like to dig in a bit further before being so dismissive. (As a bit of a hint, your argument circularly assumes the existence of a forward arrow of ti…

Then again, if one is going to argue from authority, could one not equally well cite the equally stonking smart physics PhD's who dismissed the argument with "there is no physics in this paper"? And does the argument about quantum entanglement not also circularly assume the existence of a forward arrow of time?

Re: Quantum Entanglement Drives the Arrow of Time

#100
post #88

Earlier quoted context omitted.

Here's a crazy thought... the really stonking smart physics PhDs who have spent their whole lives working on this problem are perfectly aware of the classical 18th-century physics you are referencing, and they've found it an unsatisfactory explanation. Perhaps you might like to dig in a bit further before being so dismissive. (As a bit of a hint, your argument circularly assumes the existence of a forward arrow of ti…

Then again, if one is going to argue from authority, could one not equally well cite the equally stonking smart physics PhD's who dismissed the argument with "there is no physics in this paper"? And does the argument about quantum entanglement not also circularly assume the existence of a forward arrow of time?

'dismissed the argument with "there is no physics in this paper"?'

Since retracted by essentially the same authorities and it's now a bustling field, so that doesn't work very well as an argument.

And I'm pretty sure the entire point here is that the arrow falls out of the entanglement process itself, not that we first assume temporal ordering in the physics. Remember that we do get to assume the existence of time in general in this argument; the article may not have spelled it out as clearly as it could have but it did in fact observe this still doesn't solve "time" in general. It's a big result, though.

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