Re: No more talk of black holes, please!!

Lachlan - KotU <hamfish(nospam)@gmail.com> wrote:

[snip]

Naah, usually a giant star (a lot bigger than the sun) gets to the end of
its life and burns up all its fuel. The outward pressure created from energy
released by nuclear fusion is no longer strong enough to keep the star
inflated. It then collapses in on itself due to gravity. There's usually a
big explosion involved somewhere (a supernova) then what's left collapses in
even further. If there's enough mass, it compresses into an object dense
and heavy enough that its gravity is so strong that even light cannot escape
from its surface or from a certain distance around it (the event horizon).
This is what astronomers call a black hole.

That is an untestable guess as to how the things form - it's not a
theory.

And what Hawking's work in the 1970s demonstrated did not exist - since
the objects that got mistaken for `things that not even light can escape
from' radiate photons all the time according to his theoretical
predictions; it's not that there's nothing there, but that the objects
concerned do emit light. It's called Hawking radiation these days.

However, the ones which could theoretically be created by the LHC are
different in that they are tiny toty. Here's what wikipedia says about them.

It also mentions that they evaporate instantly - assuming that Hawking's
right.

"The existence of a small black hole of this mass is purely hypothetical
but if primordial black holes exist, they might reach this condition as
the final stage of runaway evaporation due to Hawking radiation. If
Hawking Radiation is real, then small black holes would radiate away
matter as pairs of virtual particles emerge from the vacuum near the
event horizon, with one falling into the black hole, and the other
wandering away, with the net result that the black hole loses mass [due
to conservation of energy]. Under Hawking's theory, this "evaporation"
rate would increase as the black hole lost mass, eventually resulting in
a micro black hole that would suddenly explode in a burst of particles."

[snip]

Rowland.

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