[Fluid_thinker (OP)]

If you take an entangled pair of photons and send one into a black hole, what happens?

Is all information lost in the black hole?

Would there still be entanglement? If so does that mean that information is still conserved inside the black hole?

[Soul Surfer]

An interesting thought.  This process is in effect the source of the Hawking radiation from the black hole.  a virtual pair of entangled photons forms at the event horizon one falls in and the other escape to be detected.  unfortunately the question cannot be answered experimentally and a definitive answer will only be possible when we fully understand the process of entanglement.  My guess is that the quantum rules will still apply but this may mostly be associated with the fluctuations in the event horizon that originated the pair of photons in the first place.

[JP]

Is it a question of understanding entanglement or understanding black holes?  Two particle entanglement is about measurements of one particle placing requirements on what you can measure on the other particle, so you should only know your particles are entangled when you compare measurements on the both of them.  If you've tossed a particle into a black hole, you can't meaningfully talk about comparing measurements of the two particles. 

The big question (that Hawking and others are working on) is if you can recover that information from the particle that fell in, presumably once the black hole evaporates. 

[Fluid_thinker (OP)]

So it depends if Hawking radiation actually exists.

If it does it exist, does it contain Information?

And is that information conserved information of the Entangled pair?

If it is conserved, does that mean we could know information inside the black hole?

[Vern]

I wonder if we could even determine whether or not radiation seen coming from a supposed black hole was Hawking radiation. We would expect it to derive from 50% matter and 50% antimatter. However, the antimatter wouldn't survive long in the material universe. I guess we might see an abundance of .510 MeV radiation coming from the matter-antimatter reactions.

[Soul Surfer]

Hawking radiation from normal (several solar masses or larger)  black holes could only be very cold electromagnetic or theoretically gravitational.  Because all normal particles including neutrinos are far to massive and energetic to be produced.  In fact the temperature of the radiation is well below the temperature of the cosmic microwave background radiation so such holes cannot yet decay in our universe