/sci/ - Science & Math

The state of the matter within black holes doesn't even have the structure necessary to differentiate between matter and antimatter.

Even if it did, the annihilation products couldn't escape either black hole, so the two would just combine into one bigger black hole. Mass-energy equivalence- It doesn't matter what happens inside the event horizon.

But if lots of matter and antilots of antimatter suddenly emerge from nothing and form two separate black holes and they devour one another, they do not annihilate and you essentially have disturbed the conservation laws massively? 0 = lots?

>>2117593
I'm not sure what would happen but I'm sure an anti-matter black hole is technically possible. After all, black holes can evaporate through virtual anti-particles falling into it. They might even explode when their mass is too small.

>>2117608
When virtual particle pairs emerge from the vacuum they leave a whole i the vacuum energy waves. The whole will be sucked into one black whole or the other, reducing its mass.

Here's a question though. If gravity propagates out at the speed of light, how can gravity itself escape the event horizon of a black hole?

Similarly, if a black hole is electrically charged, can that electrostatic field propagate outside the event horizon?

>>2117615

Hawking radiation has nothing whatsoever to do with the material composition of the singularity.

>>2117637
>how can gravity itself escape the event horizon of a black hole

Gravity does not stop itself from propagating. The fact that it propagates at light speed is immaterial.

>can that electrostatic field propagate outside the event horizon

Nope.

>can that electrostatic field propagate outside the event horizon?
yes, charge is one of the properties of a black hole

>>can that electrostatic field propagate outside the event horizon?
>yes, charge is one of the properties of a black hole

>>can that electrostatic field propagate outside the event horizon?
>Nope.

Wut people disagree

>>2117876
I know there are metrics specifically for charged black holes, so I'm not quite sure how the charge escapes the event horizon... or if it's charged yet the field is completely interneal to the black hole.

Antimatter has positive energy, so it would just make the black hole bigger. Any gamma rays produced inside the black hole are not going to leave.

And there wouldn't be any other differences because:
http://en.wikipedia.org/wiki/No-hair_theorem

>>2118063
There's nothing impossible about field lines crossing the event horizon. They just can't transfer any information out. The field lines are set up when the charged body falls into the black hole and they stay there.

Energy comes out of colliding black holes in the form of gravitational waves.
The faster they collide, the more energy is released.
If charge is assisting their attraction, then the faster they'll collide.
That's how some of the energy of the potential difference comes out.

Well we think anti matter and matter both exert gravity on each other despite having equal and opposite charges.

Say there was a black hole made from an antimatter star implosion (highly hypothetical) The merging of the two black holes would be entirely relative, because spacetime curvature becomes infinite beyond the event horizon and as all of the matter/antimatter has imploded into a singularity, I highly doubt that the two singularities would meet even if they were both within the schwarzchild radii of each other.

But say they did... They would annihilate into pure energy, light.... but as light cannot escape the gravity of a black hole it should just remain there, but then again, does light itself have mass and therefore that raises an interesting question: Can photons produce a gravitational field of their own?

I SAY THIS:

VE MUST TEST

Make me 3 suns worth of antimatter then imploded it near the Cygnus Black hole then get the fuck out of there and watch what happens!

>>2118196
Three possibilities:

1. You make an even bigger black hole

2. You kickstart a new big bang

3. The two blackholes repell each other for some strange reason

>>2118171
I've asked on sci before if a photon has a dent in spacetime, and someone said something about contributing to some kind of tensor, therefore yes. I didn't really understand, but someone thought so. Which would be testable by altering the path of a weak laser beam by a strong one, right?

>>2117637
Im out of my element on this, but isn't charge mediated via photons? And photons can't escape a black hole, so if a black hole does have a charge, its effects wouldn't reach outside, yes?

>>2118339
You're talking about one strong motherfucking laserbeam. e=mc^2. for one gram of mass that produces very little gravity, you need terrawatts of laser energy.
In which case either photons have negligable mass or they have no mass when in that form, although they are affected by gravity they do not affect objects with mass when flying passed them.

But when you are dealing with 3 suns worth of matter annihilating with 3 suns worth of antimatter within the confines of an event horizon where our understanding of the laws of physics go out of the window altogether.....

Can a ball of 6 sun's worth of photons contained inside a blackhole escape the black hole or will they just condense back into matter?

matter doesn't cause gravity, mass does, so it doesn't matter (no pun intended) if its antimatter or regular matter, it will still attract each other. and unless photons create a gravitational field all the light would escape as the mass in the black hole would've been reduced enough for it to cease from being a black hole

>>2118361
>photons condensing into matter
Can someone elaborate on this? I've heard in fields of high gravity, particle production is more prevalent (hawking radiation), but I've never heard that photons can condense into matter.

>>2118419
i believe hawking radiation only occurs at the event horizon of a black hole and the smaller the black hole the more radiation is emitted

>>2118361
What happens inside the event horizon is irrelevant. Just from knowing the metric outside we know nothing will escape.

>>2118437
Smaller in mass doesn't make sense to me. . . the more warped spacetime is, the more particles should be coming into existance, right? And the bigger the black hole, the more warped the spacetime?

>>2118456
well i'm not sure how the warping of spacetime creates particles but this is what i remember to be true. bigger black hole means at the center the space is more warped, but hawking radiation is emitted from the event horizon, maybe something to do with the smaller surface area of the event horizon?

>>2118494
The way it was explained to me is that the particle pairs pop into existance convert gravitational energy into mass+momentum, so thats how black holes "evaporate" by having some of its mass converted into matter, and some of the matter escaping (at the event horizon). Or I could be completely mis-remembering it. And I guess a larger black hole will have a larger perimeter of event horizon, so its warping of spacetime is spread out more, I dont know.

>>2118515
that would mean that the matter is basicly transporting from the center of the black hole to the event horizon, i think you might be "mis-remembering" it. i was under the assumption that particles like these pop in and out of existence all the time, but it is a particle and anti particle, so thats how they disappear again. but with black holes, at the event horizon, sometimes one of the particles escapes and one gets sucked in. the one that escaped is the radiation. the one that got sucked in gets annihilated b/c its antimatter. i might be remembering that wrong as well but thats my understanding of why black holes dissappear and hawking radiation occurs. correct me if i'm wrong b/c i think i am :P i dont see why the antiparticle is the one to be more likely to be pulled in while the normal one goes the opposite way, which is why i think i'm wrong

>>2118631
Yeah thats what I used to think too, so I asked why a black hole would "favor" the antiparticle to pull it in, and someone said no, its just either of the particles, since they react to gravity the same way. They said that particles can't just pop out of nothing, because that would violate conservation, they have to be in some kind of high energy field which gives them something some use in order to create their matter/momentum.

Another aspect of antimatter annihilating in the black hole is that even though it would lose a particle in the annihilation with the incoming antiparticle, it would gain energy, since it only had one particle before, but after the annihilation it would have two particles worth of energy. And if energy contributes to warping space time, then the black hole would gain mass I think?

On the other hand, if you subtract two particles worth of energy from the black hole (the two particles that are created in pair production), and one particle falls back in and returns its mass, the black hole is still -1 particle worth of energy, which is the same amount that "leaves" the black hole (the particle of the pair that DIDN"T fall in)

>>2118668
for your second part i think it would lose 3 particles every time an antiparticle fell in but 2 of those particles would get converted into gamma rays which stays in the black hole while the third, normal particle escaped.

however if an antiparticle were to escape it would only lose one particle b/c the normal particle coming back in wouldn't annihilate anything.

so either way it loses mass and gravitational strength unless photons have a gravitational field as well, which i dont think they do.

but how does the matter from the center of the black hole just dissappear and appear at the event horizon though like that? maybe i'm just missing something?

>>2118730
>so either way it loses mass and gravitational strength unless photons have a gravitational field as well, which i dont think they do.
correction, even if photons have a gravity field it would still lose one particle worth of energy in each scenario

>>2118730
I guess it all depends on if photons contribute to the gravity well of a black hole. Im starting to really think I must not be remembering it right, about the mass inside the black hole being traded for the new particles. But I definitely think the particle pair that comes into existance at the expense of something else.