gravity and its effect on OTHER fields

[bwanaaa]

how many times have people heard the definition of a black hole-an object so massive that even light cannot escape its gravitational field. If we were to refine our concept of a black hole , we might come to the idea that it has a solid core and that here is a certain distance from the surface of the core to the event horizon. In fact the phase 'solid' might not be applicaple but rather under such high gravitational conditions, it is likely that all mass is fusing and likely to be a star, so the phase is probably a plasma surrounding a fusionless solid core. but my point is that there must be black holes so massive that the event horizon is a significant distance away from the plasma's surface. let's call this distance the mantle. Can it be measured?

when a laser is shined to pass just outside the event horizon, it will bend around the black hole , just as a comet's trajectory is deflected by our earth's gravity. if the laser skims the event horizon, then the light will go into orbit around the black hole. if the laser is then aimed a hair closer towards the black hole's center, the light will then spiral into towards the center of the black hole until it hits the plasma surface. the net result is no different to an outside observer than if the laser were aimed at the center of the black hole-so light cannot be used to measure the mantle. but how about magnetism? Does a black hole distort a static magnetic or electric field? Since the mantle has no density (since it is nothing but a vacuum), it likely has no magnetic or eletrical properties, whereas the plasma is probably rocked by electromagnetic storms-like our sun's surface.

Since magnetism and electricity are stronger forces than the weak gravitational force, can we not use them to dissect the interior of a black hole- measure the mantle, etc.

 

[Braznor]

Nope,

I believe the interior of the event horizon makes collision with the singularity inevitable. Once anything is trapped inside the event horizon, the oncoming collision with the singularity is as impossible to avoid as trying to avoid the coming week i.e. space takes the role of the irreversible forward march time, only this time, the inevitable event is surpassing the space to smash with the black hole ahead.

Such a condition would interfere all fields and particles including photons.

 

[silverpig]

The answer is: no one knows. Time stops at the event horizon, yet things still seem to fall in. The result is we have no idea what goes on inside.

There are theoretically such things as charged black holes and magnetic black holes, but no one knows if they exist.

And it almost certainly is not a plasma inside the event horizon.

 

[wwswimming]

Originally posted by: silverpig
The answer is: no one knows. Time stops at the event horizon, yet things still seem to fall in. The result is we have no idea what goes on inside.

There are theoretically such things as charged black holes and magnetic black holes, but no one knows if they exist.

And it almost certainly is not a plasma inside the event horizon.

we have an approximate idea that things get crushed into,
to use the Monty Python term, "tiny bits".

no one has come out the other side, except, perhaps,
7 of 9. (on Star Trek)

 

[AnnonUSA]

I can think of a few people I would like to send in there to try and find out.....

 

[bwanaaa]

Originally posted by: silverpig
...
There are theoretically such things as charged black holes and magnetic black holes, but no one knows if they exist.

And it almost certainly is not a plasma inside the event horizon.

over time, a feeding black hole will pull the heavier protons in farther towards its center than the electrons of the matter it consumes.

since the electrical force is greater than the gravitational force, a black hole should be negatively charged on the outside-the heavier protons being pulled in beyond the event horizon, The mantle and event horizon having a net negative charge. beta particles should therefore not accelerate towards a black hole as fast as neutron , and alpha particles should accelerate even faster. cannot this be observed?

 

[Braznor]

Originally posted by: bwanaaa

Originally posted by: silverpig
...
There are theoretically such things as charged black holes and magnetic black holes, but no one knows if they exist.

And it almost certainly is not a plasma inside the event horizon.

over time, a feeding black hole will pull the heavier protons in farther towards its center than the electrons of the matter it consumes.

since the electrical force is greater than the gravitational force, a black hole should be negatively charged on the outside-the heavier protons being pulled in beyond the event horizon, The mantle and event horizon having a net negative charge. beta particles should therefore not accelerate towards a black hole as fast as neutron , and alpha particles should accelerate even faster. cannot this be observed?

Gravity overwhelms the electromagnetism field at the scale of black holes. The escape velocity of any particle would need to be greater than the speed of light which is impossible under Einsteinian conditions. To achieve such a velocity, we would need energy input of infinity for anything with a fraction of mass. Therefore nothing with mass or even electro magnetic radiation can escape the singularity.

There are no electrons or protons inside the black hole. All of it is crushed into godknows what.

So a black hole should attract all matter or radiation unlucky to be trapped inside the event horizon into a dense (infinitely?) small ball of matter of unknown proportions. Space time is bent severely at this point. Not much can be said with certainty about the conditions prevailing here as it remains in a very grey area of physics i.e where the biggest meets the smallest.

But one thing for sure, if a black hole indeed possess a charge, it should still gobble similarly/opposoitely charged matter without the slightest chance of the charge affecting the rate of gobbling up. Just the actual charge of the black hole may get affected.


Also there should be hawking radiation at the edge of the event horizon. This has not been confirmed, but I shall explain.

At the very edge of the event horizon, the constant virtual particle-antiparticle annihilation as assumed to happen in the vacuum of space (under quantum theory) gets interrupted. At the very edge of the event horizon, one particle of the virtual particle-antiparticle pair finds itself unlucky enough to be one th wrong side of the event horizon and collapses inside the black hole. The other particle of the virtual pair (freed from the cycle of annihilation) manages to escape slowly into space.

To conserve the total amount of energy in this universe, the particle which has fallen inside the black hole is assumed to have negative 'energy' which in turn decreases the mass of the black hole. This is turn causes the black hole to evaporate away eventually. Note that the rate of evaporation is inverse to the mass of the singularity.

Therefore, a black hole with a lighter mass will evaporate away faster than a black hole with a heavier mass. The smaller the singularity, the quicker its destruction and the brighter it will appear to be.

 

[Biftheunderstudy]

@Silverpig Now I know your an astrophysicist so you probably already know this but for the benefit of others..

Time only stops if you are viewing the event horizon from infinity, the schwarzschild metric has a coordinate singularity at r_s, switching to a different coordinate system can remove this singularity and thus allowing particles to continue to travel towards the true space-time singularity at the center(r=0). What this means is that you don't have stuff accumulating at the event horizon because time stops there, it continues on to the center like normal. Secondly the metric used is actually similar to the schwarzschild metric, all you have to do is swap the roles of space coordinates with those of time and visa versa and you get a unique solution.

Now to the meat and bones..

There are many interesting theories involving charged black holes and rotating black holes. Look up Reissner-Nordström black hole and Kerr black holes. Very interesting stuff including the possibility of escaping a black hole after passing through the event horizon(s).

 

[bwanaaa]

@Braznor


from your somewhat rambling reply, i sense that you are a little upset/frustrated. my specific question was measuring the velocity of differently charged particles towards black holes. granted, the event horizon and interior are completely up to one's imagination-whether there is a mantle and whether light orbits the black hole at the event horizon are presently unknowable..light and therefore information as we know it, does not leave the hole. However, at a certain distance outside the event horizon where gravity is great, particles will be accelerated towards the black hole. was it galileo or newton or my science teacher who said that a bocci ball and a watermelon dropped from the tower of Pisa hit the ground at the same time- i dont remember.

but if the ground is positively charged (say just before a lighting strike) and the bocci ball is negatively charged (from the VandeGraf generator you brought up there with you) while the watermelon is positvely charged- then-well, you get the idea.

back to paticle physics, if you accelerate alpha particles gravitationally, will they not emit a different em signature than accelerating beta particles(i,e, a different frequency)? you might see this radiation as some of it radiates away from the vicinity of the hole. if the radiation signatures are doppler shifted apart from each other (or towards each other) from the expected pattern, then, isnt that evidence that a black hole is charged?

@Bitofunderstudy
thank you for your reply.

@silverpig
please tell me why there is 'almost certainly' no plasma inside the event horizon-what else do you call 'matter soup'?

 

[Biftheunderstudy]

In all likelihood its a quark plasma since thats the most fundamental constituents but realistically we have no clue. The radiation we're looking for would be extremely hard to see since the black hole will most likely have an accretion disk which will have tons of accelerating charged particles. This makes a specific sort of spectrum of cyclotron radiation, an accelerating particle through gravity being repelled by the charge on the hole itself would probably be lost in the overwhelming signal.

Just wiki those two types of black holes and you should get some ideas. The jist of it is that black holes can by definition only have 3 properties: mass, angular momentum and charge. They are in fact the largest elementary particles we know.