quantum determination question

[hoola]

if alice determines an up and that delivers a down measurement for bob, what if they determine their respective particles at the same instant in time, should that somehow be made to happen, and would that matter to the outcome?

[MigL]

At the same instant in time ?
You mean imultaneously ?

"According to the special theory of relativity, it is impossible to say in an absolute sense that two distinct events occur at the same time if those events are separated in space."

From      Relativity of simultaneity - Wikipedia

[hoola]

yes, but we are dealing with a quantum function, and that "it knows no time" and not restrained by relativity

[MigL]

But observations and experiments are ...

[hoola]

right, but if the measurements were somehow not (as a pure thought experiment) restrained by relativity, would outcomes be any different?

[swansont]

22 minutes ago, hoola said:

right, but if the measurements were somehow not (as a pure thought experiment) restrained by relativity, would outcomes be any different?

Once you postulate violating physical law, you can’t draw any valid conclusions about what happens. You’ve decided physics doesn’t apply.

[hoola]

right you are

[bangstrom]

13 hours ago, hoola said:

if alice determines an up and that delivers a down measurement for bob, what if they determine their respective particles at the same instant in time, should that somehow be made to happen, and would that matter to the outcome?

Experiments such as the one you are asking have been done many, many times and with greater accuracy over the years. The observations are that A and B can't be far enough apart and the measurements can't instant enough to change the expected outcome. By comparing the shortest times between measurements and the distance between A and B  it is possible to find a lower limit for the time of the interaction compared with c.

https://newatlas.com/quantum-entanglement-speed-10000-faster-light/26587/

https://www.scientificamerican.com/article/china-shatters-ldquo-spooky-action-at-a-distance-rdquo-record-preps-for-quantum-internet/

https://www.newscientist.com/article/2134843-chinese-satellite-beats-distance-record-for-quantum-entanglement/

"Quantum entanglement, one of the odder aspects of quantum theory, links the properties of particles even when they are separated by large distances. When a property of one of a pair of entangled particles is measured, the other "immediately" settles down into a state compatible with that measurement. So how fast is "immediately"? According to research by Prof. Juan Yin and colleagues at the University of Science and Technology of China in Shanghai, the lower limit to the speed associated with entanglement dynamics – or "spooky action at a distance" – is at least 10,000 times faster than light."

[Eise]

26 minutes ago, bangstrom said:

at least 10,000 times faster than light

Psst... It is faster than thought...

[joigus]

1 hour ago, bangstrom said:

According to research by Prof. Juan Yin and colleagues at the University of Science and Technology of China in Shanghai, the lower limit to the speed associated with entanglement dynamics – or "spooky action at a distance" – is at least 10,000 times faster than light."

I'm afraid Mr. Juan Yin --and yourself-- are gonna have to do better than that.

If I ask two students, one in Shanghai, and another in Massachusetts --at the same time in a given inertial reference frame-- at which speed the Pythagorean theorem is verified, they will find the speed is infinite. How could that be?: Because the truth of the theorem was already encapsulated in their respective minds long before they performed the measurement.

What you say only proves there are people in Shanghai wasting millions of Yuan in measuring very stupid things.

It's happened before.

[bangstrom]

On 10/16/2022 at 8:15 AM, joigus said:

Because the truth of the theorem was already encapsulated in their respective minds long before they performed the measurement.

You appear to be saying that what the experimenters think determines the outcome of the experiment. The sort of experiment mentioned in the OP was the experiment that won the Nobel for Aspect and Clauser. Clauser was certain that the experiment would support local realism and locality as found Einstein's EPR paper but it failed to do so.

[joigus]

3 hours ago, bangstrom said:

You appear to be saying that what the experimenters think determines the outcome of the experiment. The sort of experiment mentioned in the OP was the experiment that won the Nobel for Aspect and Clauser. Clauser was certain that the experiment would support local realism and locality as found Einstein's EPR paper but it failed to do so.

You're confusing correlation with causation. That's not what I'm saying. The experimenter's minds are determined by a common cause, either in the past --exactly as in the singlet state-- or not. Only state of affairs is more complicate in the case of the singlet.

Confusing of correlation with causation can be very, very misleading. Sometimes, not even causal connection in the past can be significantly attributed.

For causation to be attributed, you must have a theory for the common cause.

[bangstrom]

4 hours ago, joigus said:

You're confusing correlation with causation. That's not what I'm saying. The experimenter's minds are determined by a common cause, either in the past --exactly as in the singlet state-- or not. Only state of affairs is more complicate in the case of the singlet.

Confusing of correlation with causation can be very, very misleading. Sometimes, not even causal connection in the past can be significantly attributed.

For causation to be attributed, you must have a theory for the common cause.

 

4 hours ago, joigus said:

You're confusing correlation with causation. That's not what I'm saying. The experimenter's minds are determined by a common cause, either in the past --exactly as in the singlet state-- or not. Only state of affairs is more complicate in the case of the singlet.

Confusing of correlation with causation can be very, very misleading. Sometimes, not even causal connection in the past can be significantly attributed.

For causation to be attributed, you must have a theory for the common cause.

Correlation is an effect, not a cause. What do you think is the cause of correlation?

[joigus]

1 minute ago, bangstrom said:

Correlation is an effect, not a cause. What do you think is the cause of correlation?

Of what? Of number of people drowning by falling into a pool and Nicholas Cage appearing in a film?

[swansont]

3 hours ago, bangstrom said:

Correlation is an effect, not a cause. What do you think is the cause of correlation?

It can be that there is a common cause for two bits of data that results in correlation. But correlation may just be a statistical fluke, with no cause. Thus not an effect.

 

[StringJunky]

37 minutes ago, swansont said:

It can be that there is a common cause for two bits of data that results in correlation. But correlation may just be a statistical fluke, with no cause. Thus not an effect.

 

Like this?

 

[swansont]

3 hours ago, StringJunky said:

Like this?

 

The cat is clearly a Jedi knight, and those are also not the droids you’re looking for.

[joigus]

On 10/20/2022 at 11:20 PM, StringJunky said:

Like this?

Well, one single ocurrence doesn't tell you anything. That's a very important point. It's easily dismissed as a coincidence.

OTOH, if every single time you saw a particular cat doing that, you would have to conclude it's likely not a coincidence.

If you saw that happen with the same cat every single time, maybe a natural hypothesis would be that the owner of both the cat, the TV set, and being in control of the sequences shown to that cat, has arranged things in such a way that the cat has been trained to recognise the situation and produce the desired effect.

Conclusion: Coincidence is not such. There's been an antecedent common cause to give rise to observed correlations.

If, OTOH, every single cat you try this with displayed same behaviour... Well, that would be a puzzle. Every time the correlation becomes more and more puzzling, because you widen the sampling, and it becomes less and less likely that it be a coincidence.

You would have both to widen your statistical scope --perhaps invoke Bayesian methods--, have a theory to explain why this would happen, further test your theory by sampling more and more of the parameter space that your theory suggests, etc.

[hoola]

it seems as though two signals  (matter waves) in an entangled particle situation are operating in a destructive fashion, and in a sense, don't exist in a normal context. The act of observing either wave directly seems to shield each signal from the other, ending the destructive effects, allowing them to manifest into individual real matter particles, based upon the information in the original matter waves. The fact that the resultant particles are necessarily of opposite spins is due to the matter waves having been 180 deg. out of phase in the original scenario.

Edited October 24, 2022 by hoola

[hoola]

^{in order to maintain non locality in this scenario,  the matterwaves are parallel, and  inductively proximate so as to enforce destructive interference, and when one particle is interrogated, the spatial distance between waves is increased sufficient to allow them to ignore one another for individual particle creation. This infers a syncronos recovery of the particles if the gap separation increase is instantaneous  along the length of distance between particles.}

[hoola]

the idea of the gap widening along the entire length can be modified as to:   gap widening close to either termination of the matterwaves of sufficient length to contain enough information to describe the particle completely, and that no energy to the system other than the initial interrogation of either particle is needed for the mechanism to work.

Edited October 24, 2022 by hoola