If electromagnetic radiation cannot escape the gravity of black holes, why do x-rays spawn from black holes?

JMG.

are you familiar with Hawking Radiation?

in brief, QM states that there are virual antiparticle pairs (both positive and negative) created in space. when one is created near a singularity, one will enter, allowing the other to be emitted as radiation.

As matter falls into a black hole, it spins around in an accretion disk, becoming extrmeley hot and thus emitting x-ray and other forms of radiation. This accretion disk of course lies outside the event horizon--the "point of no return"--and thus the x-rays can excape and not get sucked into the hole.:)

RIght x-rays are emitted by the frictional forces in the accretion disc of a black hole which is a good wway to oberve a black hole, but tis happens before the matter s past the vent horizon.

Hawking radiation is the mechanism that makes black holes compatible with thermo dunaics and is the influx of negative energy (via virtual particles) into a black hole that cause emmisions of x-rays just outside the event horizion. Howver this effect is tiny and IIRC correctly for a black hole 1 solar mass only gives a surface temp. of about 10^-9n degrees which gets a lot, lot less with the size of a black hole meaning it'snot a great way to detect black holes.

The best way to observe them is their gravitational effect on other bodies esp. in binary systems.