Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Dharmansh on 27/11/2012 09:14:53

Title: Black Hole
Post by: Dharmansh on 27/11/2012 09:14:53
How is Black Hole Created n how it work?n how gamma burst are made inside the black hole?
Title: Re: Black Hole
Post by: evan_au on 27/11/2012 10:12:00
A black hole forms when the density of matter gets so high that the escape velocity exceeds the speed of light. According to our current understanding, nothing can travel faster than light, so the expectation is that nothing can escape from within a black hole's event horizon.

A common way for black hole to form is if a star exceeds about 4 times the mass of the sun, in which case matter cannot withstand the gravitational force, and it will collapse to a black hole. http://en.wikipedia.org/wiki/Black_hole#Gravitational_collapse

Matter passing by the black hole will form an accretion disk outside the event horizon, reaching extremely high temperatures that emit X-Rays.

The source of Gamma Ray Bursts is somewhat debatable, and may originate in a variety of high-energy events. Supernova explosions that result in formation of a black hole, and a black hole swallowing a star are two of the candidate sources. In both these cases, the energy is released near the black hole, but outside the event horizon. http://en.wikipedia.org/wiki/Gamma-ray_burst 

So we don't actually see something happening inside the black hole.
Title: Re: Black Hole
Post by: Dharmansh on 27/11/2012 12:41:00
But i have heard that Some light is reflected from Black hole is it ryt?
Title: Re: Black Hole
Post by: imatfaal on 27/11/2012 16:54:58
Dharmansh - no light is reflected, but there are interesting effects to do with the intense gravitation.

1.  Hawking radiation - the black holes actually emit a radiation through complex quantum mechanical processes.  For actual blackholes this radiation is so longwave that the apparent temperature of the blackhole is actually lower than that of empty space - so normal blackholes are not net emitters in the present universe.

2.  Accretion Disks - as Evan explained above

3.  Light emitted from distant objects is bent by the blackhole - as it is by any massive object. 
Title: Re: Black Hole
Post by: Dharmansh on 28/11/2012 10:24:27
I have created a theory for black hole.....can it help us or no?
Title: Re: Black Hole
Post by: simplified on 28/11/2012 13:14:04
I have created a theory for black hole.....can it help us or no?
I don't think you have created useful theory,but method of creation of theory could be interesting.
Title: Re: Black Hole
Post by: syhprum on 28/11/2012 15:45:47
Some thing similar to reflection could occur if a Photon approaches a BH and does a partial orbit of 180° and comes back towards you, am I describing anything feasible ?
Title: Re: Black Hole
Post by: Dharmansh on 29/11/2012 09:35:21
Thanks simplified ,syhprum ,evan_au ,imatfaal........i hav another question.....can v make theory without Equation?or equation is compulsory?N how to publish our own theory or process of publishing our own theory ?
Title: Re: Black Hole
Post by: JP on 29/11/2012 15:50:10
Thanks simplified ,syhprum ,evan_au ,imatfaal........i hav another question.....can v make theory without Equation?or equation is compulsory?N how to publish our own theory or process of publishing our own theory ?


Hi Dharmansh,

I noticed you asked the same question in two places.  Please try to ask a question only once on the forum.  It helps us keeps things organized.  I've also moved this question to "General Science" since it's not purely a physics question.
Title: Re: Black Hole
Post by: Dharmansh on 18/02/2013 11:06:27
Is there any unanswered question about black hol?....if yes plzz post here...thank u