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Colin Earl asked the Naked Scientists: Question: Why does Hawking (black-body) radiation not prevent the formation of singularities? The following argument for why singularities cannot form seems too obvious to be correct, but I cannot see the flaw. I would be very happy to offer $25 to the first solid explanation of why it is wrong. Hawking radiation has a temperature T, given by the formula T=hc/(4 * 3.141â€¦ * R * k) (see ...sorry, you cannot view external links. To see them, please REGISTER or LOGIN (3D)) So T is proportional to 1/R where R is the radius of a black hole event horizon. However, the horizon is not a hard physical boundary, so the Hawking effect presumably continues to operate and drive ever increasing temperatures as matter falls towards the center of the hole. The amount of energy produced by a black body at a given temperature is proportional to T**4 and exerts the same outward pressure on incoming particles as that which balances gravity in our sun. If T is proportional to 1/R and if the amount of energy produced is proportional to T**4, incoming matter will there experience a repulsive force proportional to 1/R**4 which will eventually balance a gravitational pull that only increases at a rate of 1/R**2. So equilibrium will be reached before incoming matter reaches the hole center and no singularity will ever form. This argument also provides a cut-off-point that allows gravity to be combined with ordinary quantum mechanics without encountering singularities. Of course, it all hinges on the choice we made to use a formulation where T depends on 1/R, rather than depending on 1/M where M is the mass of the hole. If this is the reason why it is invalid, it must be that process which generates Hawking radiation on the event horizon is not dependent on the radius of curvature at that point but on some other characteristic of the hole that distinguishes that point from one on another hole of different mass. If so, what property is it? If not, what exactly is the error in the above argument? Best regards, What do you think?

A Hawking radiation is presumed as a result of the Black Holes event horizon already existing, as far as I know? You can't assume the radiation to come into play before the event horizon. A event horizon is also a observer dependent phenomena, also depending on what type of Black Hole you refer too. A 'gravitationally accelerating/free falling observer' won't see a Hawking radiation.We had a nice discussion about Hawking radiation and Unruh radiation here. They seem as very similar effects to me.Read it and see what you think.