Wave function collapse of entagled particles - when one is inside the event horizon

[Dr. Jekyll]

I didn't know if I should put it here or in the Relativity forum, I suppose this is a more suiting place.

 

I'm kinda rusty regarding general theory of relativity, but as I got it (as I remember) it is not possible to get a relation between an event/"time" inside the event horizon and time outside. For instance, for an observer outside the blackhole nothing will ever pass the event horizon.

 

Now suppose A and B are two persons, outside the event horizon of a black hole. They each have a particle a and b respectively, and the particles are entangled.

 

Person B starts moving towards the black hole, and when he passes the event horizon he will perform a measure on his particle b.

 

At what point does the wavefunction collapse (with respect to person A outside the event horizon)?

 

Person B can not send back any info to person A, so really, particle a will hypotethically be in any state until we can measure it.

 

Doesn't this put a bit of "flaw" to quantum mechanics? I mean, that particle a and particle b allready had a given state initially and that the superposition is just a mathematical description.

[Klaynos]

Person A's wavefunction will only collapse when they measure particle b. You don't need an event horizon for this to be true, you can do it with people in two separate rooms.

 

It should of course be noted when talking about black holes, relativity and QM that inside the event horizon we just don't have a clue wtf is going on.

[Dr. Jekyll]

Person A's wavefunction will only collapse when they measure particle b. You don't need an event horizon for this to be true, you can do it with people in two separate rooms.

 

It should of course be noted when talking about black holes, relativity and QM that inside the event horizon we just don't have a clue wtf is going on.

 

As you say, person As wave function will only collapse when B measure particle b. Now, "when" is that? It is not possible to transform a time t1 inside the event horizon to a time t2 outside the horizon. So "when" does the wave function collapse, with respect to A. That is, when is particle a not entangled anymore with particle b?

[Klaynos]

No, I'm saying that person A's will only collapse when they measure particle a. Whereas person B's has been callapsed from the moment they measure b... so if A wait 10000 years their wavefunction will still be in a superpositon.

 

For person B they are not entangled when they measure the wavefunction of b. For person A it is when they measure it...

[Dr. Jekyll]

No, I'm saying that person A's will only collapse when they measure particle a. Whereas person B's has been callapsed from the moment they measure b... so if A wait 10000 years their wavefunction will still be in a superpositon.

 

For person B they are not entangled when they measure the wavefunction of b. For person A it is when they measure it...

 

I came up with this example to motivate kinda what you are saying. HOWEVER, what do you base that statement on? For entangled particles there is just one wave function, having both particles in a super position. When a measure is performed (the system is disturbed), the wave function collapse; and each particle will be in a given state.

 

Your statement is kinda like the following scenario: Let a red and blue ball lie in a box. Without looking, person A takes one ball and person B the other. Then they travel 99999^99999 km from each other. If person A looks as his ball he knows what color person B has, and similar if person B looks. If person B never looks at his ball, its color will never be known.

 

Now, this is not a "spooky action at distance" in a QM sense. It is just common sense. As I recall, according to QM, it is possible to alter the outcome by measuring around different axes (Bell's Theorem). That is, if person A measure his ball in one way he will get RED, when he measure it in another way he will get BLUE. And person Bs ball will automatically "get the opposite color." And person B can do the same. That is, each persons ball is "both red and blue" until the measure is made. When a measure is made, the wave function collapse and each ball will have a color.

 

HOWEVER, this is what QM states. With my scenario posted earlier, I would like to propose that there is no "spooky action" at distance. Each ball will have their color (the super position is just a mathematical description), not depending on who or when the measure is made.

 

Isnt it all just depending on how you compare a measurement? Like, there are no upside down or right turned apples, until you compare them given a reference frame.

[Riogho]

But for person B, inside the event horizon he will know the handedness of both particles, whether person A realizes it or not. At that moment neither will be in Superposition. Two entities do not have to know the information, as long as it is evident for one.

[Dr. Jekyll]

But for person B, inside the event horizon he will know the handedness of both particles, whether person A realizes it or not. At that moment neither will be in Superposition. Two entities do not have to know the information, as long as it is evident for one.

 

Yes, but thats just an implication of the scenario I presented with "Two persons takes a ball, and one choses not to examine what color it is." That is not what the EPR-paradox/Bell's Theorem is about. If it is, it is not a paradox, since its just a statistical/mathematical assumption, having nothing to do with what is "really" happening. Which is what I wanted to show by presenting this scenario.

[Riogho]

Without taking the measurement the information doesn't exist. That is why it is both red and blue, not red or blue.

[Dr. Jekyll]

Without taking the measurement the information doesn't exist. That is why it is both red and blue, not red or blue.

 

With that approach, there is no (EPR) paradox at all. It is just a matter of what you observe, since both particles already have their given state initially, hidden variables solves the puzzle. I.e., each particle had an initial value that never changed. The wave function is just a mathematical/statistical description that has nothing to do with what is REALLY going on.

[Klaynos]

Hasn't hidden variables been disproven?

[Dr. Jekyll]

Hasn't hidden variables been disproven?

 

Yes, but I mean that hidden variables solves that scenario. IF both particles have a given state, then we have the hidden variable scenario which has been disproven.

 

In this scenario we have that a measurement has been made, but inside the event horizon, and the conclusion is that "it has no meaning" to someone outside of the event horizon. Now, why would the measurement have any meaning/impact on the other particle, even if it was performed outside of the event horizon? Black holes are not an exception in this case, as I understood it. There is no "information" being sent from particle b to particle a (contradicting general relativity) to make the wave function to collapse, so really; is the superposition a real or artificial?

[DavyJonesLoquet]

I see your point Dr. Jekall and raise you twenty duckets since the event horizon in a portal of sub-spatial eruptions causes the particles to difract or essentially blow apart and down-cycle rapidly into sub-atomics. If said particles are entangled then they are, in fact, co-tangents of Bionic processes we call Organic Chemistry. I, therefore, would say that all particles are disrupted and discard thier shells completely unless they are super-fluidic beings that have no mattered material in the spatial field distortions of gravititaion. Gravity is essential to production of atoms since gravity needs to be present to organize a lattice or plane of event horizons in space-time field effect thoery.

[Quartile]

It is just a matter of what you[/b'] observe

 

"You" would be c in the case of person A and person B wouldn't you? But you don't have a ball, you have two eyes and a brain.

 

With that approach, there is no (EPR) paradox at all. It is just a matter of what you observe, since both particles already have their given state initially, hidden variables solves the puzzle. I.e., each particle had an initial value that never changed. The wave function is just a mathematical/statistical description that has nothing to do with what is REALLY going on.

 

The paradox still exists in a very broad sense because there are initial conditions that change almost instantaneously from our frame of reference, so probability is the best tool for studying what is probably the behavior of what are probably electrons. Doesn't sound like physics to me, either.

[Dr. Jekyll]

I see your point Dr. Jekall and raise you twenty duckets since the event horizon in a portal of sub-spatial eruptions causes the particles to difract or essentially blow apart and down-cycle rapidly into sub-atomics. If said particles are entangled then they are, in fact, co-tangents of Bionic processes we call Organic Chemistry. I, therefore, would say that all particles are disrupted and discard thier shells completely unless they are super-fluidic beings that have no mattered material in the spatial field distortions of gravititaion. Gravity is essential to production of atoms since gravity needs to be present to organize a lattice or plane of event horizons in space-time field effect thoery.

 

Excuse my "ignorance," but what have bionic processes and organic chemistry has to do with it, on this scale? What do you mean with co-tangent here; a tangent that is defined in the dual room of the tangent space to Organic Chemistry? Hehe, are you serious with that statement? Please explain that further, since it sounds like you are just reading randomly out of any arbitrary formulae collection.

 

"You" would be c in the case of person A and person B wouldn't you? But you don't have a ball, you have two eyes and a brain.

No. I would be the observer. I don't need any back up by A, B (or c?). Try explain your stand with less poetry.

 

The paradox still exists in a very broad sense because there are initial conditions that change almost instantaneously from our frame of reference, so probability is the best tool for studying what is probably the behavior of what are probably electrons. Doesn't sound like physics to me, either.

Uhm no. Inside the event horizon you can not translate "instantaneously, now, then, ..." to any given time outside the horizon.

 

That is, an event inside the event horizon will occur after an infinite amount of time for an outside observer (that is, it will never happen). Conversely, for an observer inside the event horizon, an event outside will never happen.

 

There should'nt be any "magically instantaneously" change of any entangled particle, just because it falls beyond the event horizon (in relation to its partner).

Edited June 30, 2008 by Dr. Jekyll

[alwynj48]

 

That is, an event inside the event horizon will occur after an infinite amount of time for an outside observer (that is, it will never happen). Conversely, for an observer inside the event horizon, an event outside will never happen.

 

There should'nt be any "magically instantaneously" change of any entangled particle, just because it falls beyond the event horizon (in relation to its partner).

 

My understanding is: the outside observer will not observe a particle crossing the event horizon but the converse is not true. In the time of the particle it can cross the event horizon in fininite time.

 

As to the collaps of the wave function. We do not know how it works with out even horizons so its speculation with one.

 

This is my specualtion: The particles are in cummuniction via an other dimension that appaently can bridge space and time. Given the forgoing it is not difficult for me to belive that this can be done across an event horizon. An event horizons is just an area of very curved space.

[Dr. Jekyll]

My understanding is: the outside observer will not observe a particle crossing the event horizon but the converse is not true. In the time of the particle it can cross the event horizon in fininite time.

Yes, that is correct. My bad. I'm kinda (read very) rusty on GR.