Theoretical Question about Black Holes

Alright, a black hole exists in a complete and perfect void... no light, matter... nothing. If one were to shine a light on the black hole, would it increase in size at all? I know photons don't have mass, but I was wondering if it would affect size at all?

no

no

Say yes and WIN!!

Not in the way we understand size.

Size as in mass or size as in volume?  Because it'd certainly inrease the black hole's energy.

>>6
How much volume does the singularity of a black hole have?  I always thought of them as a point with no volume.  Also, why is it that we can detect black holes based on the effect their gravity has on nearby light, I thought photons were massless & gravity was a property affecting mass?  (These are serious questions, I'm not as smart/educated as most of you)

>>7
According to the equations of general relativity a black hole has zero volume.  However, according to quantum mechanics, it's impossible for an object to have zero size.  This means that the black hole would just be as small as physically possible but not a singularity.

So really we've got two extremely well tested theories saying two completely different things and until we can come up with something better we really don't know much about the size of a black hole.

The reason that black holes, or gravity in general, effect light is because gravity bends space.  And since light is traveling through space, it's trajectory also get's altered.

The black hole itself is believed to not change size regardless of what enters it; however the radius of the event horizon increases linearly with mass.

>>8
Thank you!  That was a very well-explained response without getting too complicated.

>>1
They don't have rest mass, but they certainly induce a nonzero perturbation in the stress energy tensor (which curves spacetime, and thus generates gravity) (they have pressure and energy).

The black hole gets bigger.

>>7
Gravity curves space, etc -> light is affected by gravity.  Gravity affects a lot more than just massive objects.

>>8
QM doesn't directly prohibit 0 sized particles.  The standard model/QED/etc all assume point particles.  The fact that these theories are problematic is part of why people are attempting string theory.  If you look at an undergraduate textbook, you'll find that the solutions of the simple harmonic oscillator/hydrogen atom always assume point particles.  What a black hole singularity really is like will likely require quantum gravity.

>>9
The surface area increases quadratically with mass, but the "radius" is not well defined.  The Schwarzschild radius does increase linearly with mass, but it is a common misconception that this value is the physical radius of the black hole.

The basic problem is that the metric signature on R and T change inside the event horizon.  In other words, R becomes time and T becomes space.  In fact, one of the spacelike    dimensions (T) inside the black hole is infinite.