Blackholes Definition and 72 Threads

it's been said because of hawking radiation,black hole evaporates and vanishes..but when black hole's energy is decreased by hawking radiation,its mass is also decreased,and at some point,it will have less mass and it cannot be a black hole and it should stop emitting hawking radiation then why...

Hi friends,. If black holes absorb light also, how can it exert any gravity outside a particular region? Or something can move faster than light?

consider two parallel universes like membraines. if a black hole exists on the first universe then it vil bend the space time graph to an infinite point as we know. but since there exists another universe v can say that the bented spacetime of the above vil converge vit the unbent spacetime of...

why haven't there been any observations of planets or stars or anything near a black hole's event horizon being distorted?

Dear all, i'm very new to cosmology/astronomy branches of physics. i've one simple question. it's known that the universe is expanding and i suppose the measurement was made by Hubble for which he won the nobel prize. but also, i recently learned that there're black holes at the centre of...

Hello all, After reading about how time began at the moment of the big bang and how time ends in black holes, if there was only 1 big bang and many black holes, would times be decreasing i.e. slowing down. Any thoughts would be appreciated , thx

I am going to ask some questions based on my curiosity and my complete lack of knowledge and understanding of the Universe. My biggest hope is those answering can be understanding and patient, and not see it as an opportunity to to be arrogant. Are wormholes still a possible theory of what...

Hi there! I have not yet taken any physics courses at my high school and so am an utter neophyte to physical science but I am about to run a roleplaying game that involves superheroes, alien invasions, black holes, and weather control and I have a few questions that probably are simple to you...

The question I'm about to asked has probably asked before many times b , but I keyed in a "supermassive black holes and galaxy formation" in the PF search engine , and this question has yet to be asked: How can supermassive black holes be aid the formation of galaxies when they are suppose to...

I have a very little knowledge in physics and I am new to this forum. I have read that quantum physics is a branch of physics that deals with microscopic objects i.e. objects of extremely small size (less than 1 nanometer). I have learned that black holes are extremely small objects with close...

I just saw a wonderful NOVA special called "Monster of the Milky Way". Very well done, and I noticed how the models the have are so much better at giving us a sense of the movements of stars and galaxies over time. We really have come a long way in the last 30 years. I was left with a few...

If black holes are at the centre of each galaxy is it possible that all the matter from that paricular galaxy came from another universe through the black hole sucking in one side and blowing out the other? Transfering matter from one universe to the other. Perhaps this a natural way to...

Keeton, C. R., and A. O. Petters. Formalism for testing theories of gravity using lensing by compact objects. III. Braneworld gravity. Physical Review D 73:104032 (May 24) Source: http://www.americanscientist.org/template/AssetDetail/assetid/53359

Blackholes theory maybe incorrect?? :confused: source: http://www.newscientistspace.com/article.ns?id=dn9620&feedId=online-news_rss20

I read about experiments that modeled black holes as a liquid passing through a lavel valve at supersonic speed, the point were the water went supersonic was like the event horizon of a black hole for sound - the sound could go in but not out. They were looking for sighns of Hawking radiation...

i like astrophysics so much! But have particular interest in black holes and white holes and the big bang! In astrophysics, a white hole is a postulated celestial body that spews out matter, in other words an anti-black hole, or the time reversal of a black hole. It can be a means of...

I'm just curious about one thing. Is it possible to make or create an artificial black hole?

BlackHoles--- Things CAN get free http://dsc.discovery.com/news/afp/20040712/blackhole.html talk about a new discovery does this have any other implications on any other theories?

Hi all, this is my first thread so be nice. Ok, so I remember reading something which said that if an astronaut falls into the event horizon, his vantage point of time will slow down (due to the massive gravitational field) and will eventually halt at the event horizon. He will therefore see...

i was just wandering... at the point where gravity is strong enough to be greater than the kinetic energy of which light possesses, do photons of light actually radiate some distance from the collapsed star then slow to rest and fall back to the surface, as a cannonball being shot straight up in...

[SOLVED] IN the Future... Blackholes or Wormholes Say that in the future mankind was able to master Black hole or Worm hole technology. Kinda like in Event Horizon technologically. Is it possible to master such a power? We could develope Black Hole Vacum Cleaners, Black Hole dumps, etc. If a...

I'm asking this question to see what people think about what happens when two black holes collide.If you want,give a reason for you answer.