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Physicists Create Quantum Link Between Photons That Don't Exist at the Same Time

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Re: Physicists Create Quantum Link Between Photons That Don't Exist at the Same Time

#41
post #5
post #3

Earlier quoted context omitted.

You're only the ten millionth person to voice that desire. Sadly, the universe is not obligated to be intuitive. At this point we probably have to accept that the parts of the universe that we didn't evolve to understand are free to be as utterly weird as they want to be.

Sure, but what are the odds the universe fundamentally defies intuitive logic versus the odds our small brains currently can't see the full picture but in the meantime have invented insane (but cool) mathematical machinations? I guess it's unknowable.

I can't see any basis on which to assign the probabilities you ask for. A better question might be: on what basis do you believe that the universe should be intuitive? Why should it be so?

Re: Physicists Create Quantum Link Between Photons That Don't Exist at the Same Time

#42
post #13
post #2

At the risk of being "that guy," a few thoughts popped into my head after reading this article. I couldn't help but reflect on the possibility of us just completely misunderstanding how the universe works. It wouldn't be the first time in history. What if: Our concept of time and matter is wrong, or our idea of quantum physics is interesting and useful, but ultimately wrong. Perhaps I'm just a simpleton but part of m…

It is sobering to realize there are some things I'll never understand. But it's OK. Ignorance let's us have more fun speculating. I was wondering, are two entangled particles actually the same particle, where one or both "took a time machine" to get to the other place?

This train of thought has to have something to it. There is obviously something that is "the same". Perhaps it is something more fundamental than the photons that "generates" the photons. Or, if it doesn't "generate" them, it determines the state of them at least.

In "Many Worlds", the "something" would be the particular universe that "this instance" of ourselves ended up in.

Re: Physicists Create Quantum Link Between Photons That Don't Exist at the Same Time

#43
post #7
post #2

At the risk of being "that guy," a few thoughts popped into my head after reading this article. I couldn't help but reflect on the possibility of us just completely misunderstanding how the universe works. It wouldn't be the first time in history. What if: Our concept of time and matter is wrong, or our idea of quantum physics is interesting and useful, but ultimately wrong. Perhaps I'm just a simpleton but part of m…

I think the fundamental problem is the idea that there is more than one thing. As soon as you see there is only one thing, it's no surprise that everything is related. http://philosophy.stackexchange.com/q/4751/2992

But in that case, wouldn't physics be non-local after all? Do you believe that it is non-local?

Re: Physicists Create Quantum Link Between Photons That Don't Exist at the Same Time

#44
post #35

I'm a little baffled when articles come out claiming some weird relativity-breaking quantum effect and fail to mention that the no-collapse interpretation of quantum mechanics explains the effect easily without breaking relativity.

What's the easy no-collapse interpretation explanation?

I'm guessing Ez is referring to the Many Worlds Interpretation.

Re: Physicists Create Quantum Link Between Photons That Don't Exist at the Same Time

#45
post #2

At the risk of being "that guy," a few thoughts popped into my head after reading this article. I couldn't help but reflect on the possibility of us just completely misunderstanding how the universe works. It wouldn't be the first time in history. What if: Our concept of time and matter is wrong, or our idea of quantum physics is interesting and useful, but ultimately wrong. Perhaps I'm just a simpleton but part of m…

We're most certainly missing a lot of things. But quantum mechanics is in no way wrong. It may not be complete, but not wrong. Ontologically, there is not reason for us not to discover other things about nature that are (more) fundamental.

You sound far too certain for my liking. But IANAP.

Re: Physicists Create Quantum Link Between Photons That Don't Exist at the Same Time

#46
post #34

Earlier quoted context omitted.

Do you have any sources for experiments ruling out our universe being deterministic? I'm not questioning you. I honestly have always been intrigued with the idea. Thanks.

The standard answer is the Bell inequalities, but if you only care about deterministic vs. nondeterministic then Conway's "free will theorem" is a bit simpler. (The result is that either which quantities we choose to measure must be deterministic, or physics must be nonlocal (i.e. what we do in one place can change what we measure in another place even if the two experiments happen simultaneously), or the results of…

Nothing says we live in a local universe.

Re: Physicists Create Quantum Link Between Photons That Don't Exist at the Same Time

#48
post #35

I'm a little baffled when articles come out claiming some weird relativity-breaking quantum effect and fail to mention that the no-collapse interpretation of quantum mechanics explains the effect easily without breaking relativity.

What's the easy no-collapse interpretation explanation?

There are a few, the most realistic is the Bohm interpretation: http://en.wikipedia.org/wiki/De_Broglie%E2%80%93Bohm_theory

The basic idea is that observed decoherence is not caused by wave collapse, but is caused by interaction with noise. For example, consider the double-slit experiment. If you allow light to pass through two slits, it forms an interference pattern. If you put a detector in one of the slits, the pattern collapses.

The Copenhagen interpretation says this is because the observation collapses the waveform of the photon. The Bohm interpretation says that the photon interacted with your detector and its phase was knocked out of sync.

Re: Physicists Create Quantum Link Between Photons That Don't Exist at the Same Time

#49

Does this work only in one direction? Is there any reason to see the first measurement as causal? Could the second measurement be interpreted as causal that then propagates backward in time? I'm really trying to get at if the linear description of events in the article is just a convenient simplification, or if physicists thinks that there is time order here.

If you don't measure the first photon then the 4th one could be anything and the measurement would not do anything to the 1st photon since it does not exist any more.

Re: Physicists Create Quantum Link Between Photons That Don't Exist at the Same Time

#50

I love how at the end of all these physics articles there is always some guy who is like "O HELL YEA WE CAN USE THIS FOR QUANTUM COMPUTERS!"

Those are probably the magic words that make the state security apparatus throw wads of cash at you.
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