Hawking Radiation Help!

I'm currently studying A level physics, but I enjoy reading as much as I can on more advanced Physics, in particular theoretical physics.

I recently read into Hawking radiation and how virtual particles manifesting on the edge of a black hole's event horizon cause Hawking radiation (with one particle being sucked into the black hole whilst the other is free to radiate out).

My question is twofold; "Is it correct in stating that virtual particles used 'borrowed energy' that they 'give' back when they collide and destroy one another?" and secondly "If so, in the case of Hawking radiation when they never collide, how is this 'borrowed energy' given back, or more to the point; how is energy conserved?"

P.S. I know this isn't classical mechanics but there isn't a topic for it! :)

#Mechanics

Easy Math Editor

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Comments

When an antiparticle falls into the black hole,it causes its gravitational potential energy to decrease,where does this energy go? Well you have a new particle coming towards you!

A Former Brilliant Member - 5 years, 2 months ago

Actually, the energy is still kinda conserved. See, what happens is that when a particle-antiparticle pair is formed near the horizon, as we all know, one of them gets sucked into the black-hole and the other is kind of boosted away. As far as the energy conservation is considered, it holds true, because the particle that is theorised to enter the black hole is considered to have negative energy with respect to an observer far away.

This falling of negative energy into the black hole is what causes it's mass to decrease and forms the underlying principle for Hawking Radiation.

A Former Brilliant Member - 5 years, 2 months ago

Brilliant, thanks for clearing that up for me!

Jack Purllant - 5 years, 2 months ago

No worries!! :)

A Former Brilliant Member - 5 years, 2 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$