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Posted

Black holes in the early universe may have circumvented a law of physics to grow rapidly to colossal size. The finding could solve a longstanding puzzle over why such massive objects appeared so soon after the universe began.

 

The new analysis, by Marta Volonteri and Martin Rees, both at the University of Cambridge, UK, ties up all the important factors involved in the growth of a black hole and concludes rapid growth is possible. This might be because the black hole "swallows" the radiation generated as the hole gobbles up the matter around it, preventing a destructive explosion.

 

The puzzle first arose after astronomers spotted what appear to be monster black holes, with the mass of a billion Suns, near the edge of the visible universe. The black holes themselves are invisible, but matter falling into them is heated by friction and emits very powerful X-rays. These extreme emissions define the distant system as a quasar.

 

Because of the time it takes for the X-rays to travel from these extremely distant objects to Earth, astronomers see the quasars the way they were less than a billion years after the big bang.

All consuming

 

Until now, astronomers could not explain how the objects gathered such enormous amounts of matter in such a relatively brief time. One suggestion was that black holes in the early universe somehow overcame a law called the "Eddington limit", which normally restricts the growth of objects that are collecting matter.

 

The limit arises because if a black hole eats too quickly, the disc of matter feeding it radiates so much energy that it blows itself apart, leaving little for the object to absorb, so halting growth.

 

Some astronomers have suggested that early black holes managed to get around this law by swallowing the radiation in its vicinity before it had a chance to blow apart the disc of matter.

 

In the dense inner part of the disc, the X-rays might have a hard time travelling outward because of its frequent collisions with matter. If so, it could get pulled into the black hole along with the descending matter.

Eats, shoots out and leaves

 

But it was not clear whether even these "outlaw" black holes would grow fast enough, given other constraints that exist. For example, black holes can occasionally get kicked out of matter-rich clouds into intergalactic space, where there is nothing to eat. However, the analysis by Volonteri and Rees shows the growth can be fast enough.

 

"This growth is quite a challenge," says Stuart Shapiro, of the University of Illinois at Urbana-Champaign in the US. But the new study shows "the challenge can be met under special, but plausible, circumstances", he told New Scientist. Those circumstances include an assumption that the rate at which black holes get kicked out of host galaxies is relatively low.

 

Eventually, the black holes would go back to eating at less than the Eddington limit due to a lack of supply, says Rees: "Most holes in present-day galaxies are inconspicuous because they are starved of fuel."

 

http://www.newscientistspace.com/article/dn9530-earliest-black-holes-bent-the-laws-of-physics.html

 

So, can some physics guy explain to me if i am reading this right, does this mean that its POSSIBLE to bend the rigid laws of Physics afterall? And if the laws of Physics can be bent, then isnt it perhaps possible for us to find ways around the universal speed limit in the universe? maybe not break it but bend it perhaps?

Posted

You are misunderstanding.

 

You dont "bend" the laws of physics. If you do, it just means that our understanding of that particular phenomenon is incomplete.

 

Physics is not rigid, it is always changing as new theories come about. So this may mean for example that a way to travel faster than c will be discovered. This does not mean you are breaking a physical law (law of phyics is a term with little meaning anyway), only that our initial understanding was not complete. Its unlikely though, given our current understanding.

Posted
']You are misunderstanding.

 

You dont "bend" the laws of physics. If you do' date=' it just means that our understanding of that particular phenomenon is incomplete.

 

Physics is not rigid, it is always changing as new theories come about. So this may mean for example that a way to travel faster than c will be discovered. This does not mean you are breaking a physical law (law of phyics is a term with little meaning anyway), only that our initial understanding was not complete. Its unlikely though, given our current understanding.[/quote']

 

Tycho is right. Nature has its physics, science is our attempt to understand it. Theories and Laws are just models to understand them. If blackholes taught us something that we didn't know before, we have succeeded, not failed.

Posted

Bending is used here metaphorically. In today's universe, a black hole can only grow at The Eddington limit because the black hole would heat up the surrounding matter, helping it escape.

 

Some astronomers have suggested that early black holes managed to get around this law by swallowing the radiation in its vicinity before it had a chance to blow apart the disc of matter.

 

In the dense inner part of the disc, the X-rays might have a hard time travelling outward because of its frequent collisions with matter. If so, it could get pulled into the black hole along with the descending matter.

In other words, in those days, the galactic cores, adjacent to the black holes were dense enough for X-rays to bounce around enough so that less mass escaped.

  • 3 months later...
Posted

Not to mention Eddingtions law was not as concrete as some of the more famous laws, ie 2nd of Thermodynamics, conservation of energy. if it broke one of those, it would be quite extra ordinary to say the least, and would show a deep misunderstanding in our view of the physical world

Posted
Not to mention Eddingtions law was not as concrete as some of the more famous laws, ie 2nd of Thermodynamics, conservation of energy. if it broke one of those, it would be quite extra ordinary to say the least, and would show a deep misunderstanding in our view of the physical world

 

One needs to keep in mind that physical laws have boundary conditions, outside of which they do not work. Laws based on symmetries, implying a conserved quantity, are going to apply over a much larger range of conditions than some other laws.

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