Natural Order and Science

[Harris]

Thanks Alex, that clarified quite a bit for me. Especially the inverse square law of gravity increasing in strength, I should have remembered that. One question though, if nothing can go faster than the speed of light and not even light can escape from a black hole, then how can they evaporate by radiating random noise called Hawking radiation? Why do physicists think that this happens?

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.

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

According to Wikipedia virtual particle is only an explanatory conceptual entity that is found in mathematical calculations about quantum field theory. Virtual particles do not appear directly amongst the observable and detectable input and output quantities of those calculations, which refer only to actual, as distinct from virtual, particles.

There exist two views about the existence of virtual particles:

1. The standard Feynman view, virtual particles exist but they are shadow objects obeying Heisenberg's ΔtΔE>hbar/2 inequality

2. They do not exist; they are just another fallacy of the Copenhagen interpretation of quantum mechanics

Neither of the assumptions favour physical existence of virtual particles. Furthermore, it is only an assumption that one component of virtual particle pair has negative energy value because without this assumption mathematical equilibrium of Hawking Radiation would get disturbed in which virtual particles with negative energy play crucial role to demonstrate theoretically how black holes evaporate.

Please have a look at this webpage that holds an interesting exchange of facts on virtual particles.

https://www.quora.com/Why-do-physicists-...observable

In reality, if virtual particles are true particles which appear and disappear spontaneously (ex-nihilo) that seems to be a contradiction to:

1. “Energy cannot be created nor destroyed”

2. Relativity and causality

3. Nothing can travel faster than speed of light

I am hoping for an explanation on:

1. What virtual particles are if they really exist?

2. How they work and

3. How they are similar to quantum fluctuations?