Question: Faster Than Light?

[CraigS]

Originally Posted by Kal

With a black hole you can tell exactly where the crossover point is. Up until the event horizon the object from an observers point of view outside the black hole is still within the boundaries set by the speed of light. Once it crosses the event horizon and heads towards the singularity we cannot observe it as it travels faster than light.

Hmm .. interesting … and very creative there, Andrew.

Let me apply 'The Test'…

"The litmus test is to ask whether it has or at least, could have, transmitted information. If the answer is no, the standard reasoning goes that nothing has exceeded light speed and Special Relativity survives the test."

Hmmm … a photon which has fallen into a black hole loses information via Hawking Radiation … but this happens prior to passing through the Event Horizon (?)

Might pay that one !!
(… a bit of a play on words, all of this stuff, if you ask me though).
Thanks for your input.



Cheers

[CraigS]

Originally Posted by sjastro

Without going deeply into the mathematics, before a measurement is performed a wavefunction is a linear combination of different states.
These states are known as eigenfunctions.

It represents a superimposed state of all possible incomes. By definition it is not composed of information, as information is obtained once the observer performs a measurement.

When a measurement occurs the wavefunction is now in the from of a constant multiplied by a single eigenfunction. The constant is known as an eigenvalue.
The eigenvalue is the information as a result of the measurement.

The initial wavefunction representing an entangled state does not contain information.

Regards

Steven

Hmm..

From what I'm reading, (about the "Aspect" experiment), it appears that physicists agree that the list of possible outcomes at each of two detectors, (of entangled pairs), are identical and are correlated but there is no causation evident. This being because, in no way, can one control or predict the outcome of any particular measurement. Thus there is no message, no information whatsoever.

Very subtle interpretation here …

Cheers

[Kal (Andrew)]

Originally Posted by CraigS

Hmmm … a photon which has fallen into a black hole loses information via Hawking Radiation … but this happens prior to passing through the Event Horizon (?)

Hawking radiation is something completely different, and it doesn't come from the black hole per se, it comes from space just outside the black hole.

Particle/antiparticle pairs form all the time, and those near the event horizon have one of the pair sucked into the black hole. To preserve energy, the particle that falls into the black hole must have negative energy from an outside observers point of view.

From the point of view of no information being exchanged once it crosses the event horizon, this is true though!

[CraigS]

Originally Posted by Kal

Hawking radiation is something completely different, and it doesn't come from the black hole per se, it comes from space just outside the black hole.

Particle/antiparticle pairs form all the time, and those near the event horizon have one of the pair sucked into the black hole. To preserve energy, the particle that falls into the black hole must have negative energy from an outside observers point of view.

From the point of view of no information being exchanged once it crosses the event horizon, this is true though!

Yep .. this is why I agreed with you.
We should pay out on this one !!


Cheers