How many dimensions are there in a black hole

Re: Black Hole

The usual mathematics of black-holes has four dimentions.
Have a read through:
http://cosmology.berkeley.edu/Education/BHfaq.html
... covers the usual, makes sure you are up to speed.

http://members.cox.net/jhaldenwang/black_hole.htm
... covers the geometry inside and close outside a black-hole.
Executive summary: inside a black hold you get 3 time-like dimensions and one space-like.
You need to read the preamble carefully to understand this.

 

Re: Black Hole

I just did: after "executive summary" in post #2.
3 time-like and 1 space-like.

If you want to know what that means you'll just have to read the links.
There's no royal road for this one - sorry.
Perhaps if you told me what you want to know for?

 

Re: Black Hole

those are very useful informations and links, thanks to all, keep it up..

 

Re: Black Hole

No worries and happy hunting :)

I find that pairing references like this can help - the Berkely FAQ will help refine questions. You get all the way through it and you have a chance of understanding the Haldenwang paper ... even if you don't follow the math.

 

Re: Black Hole

No worries and happy hunting :)

I find that pairing references like this can help - the Berkely FAQ will help refine questions. You get all the way through it and you have a chance of understanding the Haldenwang paper ... even if you don't follow the math.

 

Re: Black Hole

There's a massive distance between the event horizon (which is nothing more than an optical barrier) and the hypothesized singularity.

There are theories about how black holes both accrete and shed mass. But that is not necessarily related to the formation of quasars.

Quasars are formed from the accretion disk surrounding black holes. They are considered to be early objects within the time span of universal expansion.

 

Re: Black Hole

A quasar could care less about the presumed 'singularity'. All the radiation is emitted from outside the event horizon, as has already been noted.

 

Re: Black Hole

How long would it take for something to enter a black hole, from the pov of someone well outside it?

NOte: smallest BH found has about 12km to the center, and the biggest (stellar) BH has 50-odd kms. Not that far.

The galactic-center supermassive is supposed to be 13-14million kms to it's center so there you'd be travelling a while. There is a tendancy to think of these things as super-dense as well, like stellar BHs, but that need not be the case.

 

Re: Black Hole

BHs can have mass, spin, entropy and charge ... spinning charged hole will have a magnetic field. This would be a Kerr Black Hole. You can also get a magnetic field without spin ... see:
http://burro.cwru.edu/stu/advanced/stars_blackhole.html [Broken]

As for magnets inside them - Haldenwang
http://members.cox.net/jhaldenwang/black_hole.htm
- discusses the possibility of our Universe being inside a BH. That would include magnets.

If it takes an infinite time for an object to cross into a BH, viewed from a outside, then in what sense would a BH increase it's mass over time?