RE: Natural Order and Science
February 24, 2016 at 9:20 am
(This post was last modified: February 24, 2016 at 9:21 am by I_am_not_mafia.)
(February 24, 2016 at 8:10 am)Alex K Wrote: p.s. with Einstein, it is only approximately an inverse square, because gravity itself begets gravity in Einstein theory, which is not a thing in Newton theory. This means that once gravity gets strong enough, it boosts itself until it becomes more severe more quickly than a simple inverse square would. Hence you get extreme phenomena such as black holes.
Bloody hell I didn't know that at all. Hence the reason I suppose that calculations of black holes require the use of infinity. Does anyone have any ideas as to why this is a feature of gravity?
(February 24, 2016 at 8:10 am)Alex K Wrote: The derivation that is most illustrative is as follows: near the event horizon, quantum field theory makes it so that pairs of virtual particles appear. Usually, if nothing is nearby, they would simply disappear again and nothing happens. If they appear near the horizon, it can happen that one of them falls behind the horizon, whereas the other one can leave. What we see as hawking radiation is then the one that got lucky
One might now wonder why something falling in can let a black hole decrease. Now, virtual particles are not bound by E = m c^2, and if a pair appears ex nihilo, one of them will in fact carry negative energy to balance out the positive energy of the other. Only events where the negative-energy one falls in will actually happen. We did the calculation in my relativity lecture, but that was 11 years ago and I forgot how the details went
Can I just say that Physics, or rather than universe, is fucked up.
