If You Thought Quantum Mechanics Was Weird, Check Out Entangled Time

[beenherebeforeagain]

Well, if you miss it, you can always go to Heisenberg's lecture, but if you find the lecture hall, we don't know when it starts, and if you figure out when it starts, we lose the hall... that's bureaucracy for ya'.

wish I could give that a winner as well as a funny

 

[Polymath257]

I seem to remember reading about this some time back. Hopefully Polymath will chime in, as he has far more expertise than most, on the subject.

I also seem to remember reading about quantum events, where the "cause" happens after the "event" in question, a kind of causal reversal.

As the famous physicist, (Feinman?) quipped: "If you think you understand quantum mechanics, you don't."

All the problems people have with quantum mechanics ultimately come from wanting a classical description involving particles with definite properties and at definite locations at all times.

But quantum mechanics is an inherently probabilistic description of things. It is not, ultimately, a causal description. yes, things we do will affect the *probabilities*, but we cannot determine which specific property will show. We can only determine the probabilities and correlations between those probabilities.

In the 'causal reversal' experiments, there is no actual reverse causality. There are correlations and those correlations proceed forward in time at all points. Furthermore, the correlations do not transport faster than light.

So *any* claims of faster than light communication from entangled particles is simple garbage and a fundamental misunderstanding of what is going on.

Similarly, in the scenario of the OP, the correlations are moving forward in time and the interactions between 2 and 3 affects the correlations. So, because 1 and 2 were correlated, and since 3 and 4 are correlated, any induced correlation between 2 and 3 produces a correlation between 1 and 4.

Like I said, you get problems when you try to describe quantum mechanical systems in terms of classical notions of particles. But, quantum mechanics is the description that *replaced* the classical one. So attempting to have a classical description is to attempt to describe the system with the old, outdated and *wrong* descriptive apparatus. So, OF COURSE, you will have troubles.

Do I think there are interesting metaphysical issues here? Absolutely. And one huge lesson is that classical metaphysics is simply wrong.

 

[Bob the Unbeliever]

I first heard that comment on Doctor Who several years ago,. I dont dont i heard it since then until tonight when its been twice in less than an hour. The 2nd X-men was showing on TV, as it ended the announcer said "there will be more timey-wimey stuff tomorrow with men in black 3". And then you mention it. Weird or what?

<sonorous voice>

It.... Is... A... Message... From.... Zod.

 

[Bob the Unbeliever]

All the problems people have with quantum mechanics ultimately come from wanting a classical description involving particles with definite properties and at definite locations at all times.

But quantum mechanics is an inherently probabilistic description of things. It is not, ultimately, a causal description. yes, things we do will affect the *probabilities*, but we cannot determine which specific property will show. We can only determine the probabilities and correlations between those probabilities.

In the 'causal reversal' experiments, there is no actual reverse causality. There are correlations and those correlations proceed forward in time at all points. Furthermore, the correlations do not transport faster than light.

So *any* claims of faster than light communication from entangled particles is simple garbage and a fundamental misunderstanding of what is going on.

Similarly, in the scenario of the OP, the correlations are moving forward in time and the interactions between 2 and 3 affects the correlations. So, because 1 and 2 were correlated, and since 3 and 4 are correlated, any induced correlation between 2 and 3 produces a correlation between 1 and 4.

Like I said, you get problems when you try to describe quantum mechanical systems in terms of classical notions of particles. But, quantum mechanics is the description that *replaced* the classical one. So attempting to have a classical description is to attempt to describe the system with the old, outdated and *wrong* descriptive apparatus. So, OF COURSE, you will have troubles.

Do I think there are interesting metaphysical issues here? Absolutely. And one huge lesson is that classical metaphysics is simply wrong.

Thanks for sorting that out!
I expect what I read, had been written by a "pop sciency" writer.

 

[Polymath257]

Thanks for sorting that out!
I expect what I read, had been written by a "pop sciency" writer.

One of my pet peeves is the woo woo discussions of quantum mechanics that get pretty much everything wrong.

If someone has never solved a differential equation, they don't understand even the basics of QM. If they don't know what a Hermitian operator on a Hilbert space is, they don't know anything past the basics.

 

[Subduction Zone]

<sonorous voice>

It.... Is... A... Message... From.... Zod.

I don't think so. Now I love the Prophet of Zod, but I do not see this in his repertoire: