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Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: jeffreyH on 09/04/2015 01:12:18

Title: Is Hawking radiation a red herring?
Post by: jeffreyH on 09/04/2015 01:12:18
Hawking radiation is said to be due to a particle, anti-particle pair with one of them falling through the horizon while the other escapes. Presumably one will annihilate, the anti-particle, while the other continues to exist. In which case the annihilation could be either inside or outside the horizon, meaning things could be evenly balanced resulting in no net loss of mass from the black hole. How is this viewpoint wrong?
Title: Re: Is Hawking radiation a red herring?
Post by: Ethos_ on 09/04/2015 03:27:42
Hawking radiation is said to be due to a particle, anti-particle pair with one of them falling through the horizon while the other escapes. Presumably one will annihilate, the anti-particle, while the other continues to exist. In which case the annihilation could be either inside or outside the horizon, meaning things could be evenly balanced resulting in no net loss of mass from the black hole. How is this viewpoint wrong?
Wikipedia has this to say about Hawking radiation:

According to Wikipedia, the virtual particle which fell in has a negative energy and to preserve total energy the black hole will loose mass. This process is described as a quantum tunneling effect.
Title: Re: Is Hawking radiation a red herring?
Post by: jeffreyH on 09/04/2015 13:33:02
Hawking radiation is said to be due to a particle, anti-particle pair with one of them falling through the horizon while the other escapes. Presumably one will annihilate, the anti-particle, while the other continues to exist. In which case the annihilation could be either inside or outside the horizon, meaning things could be evenly balanced resulting in no net loss of mass from the black hole. How is this viewpoint wrong?
Wikipedia has this to say about Hawking radiation:

According to Wikipedia, the virtual particle which fell in has a negative energy and to preserve total energy the black hole will loose mass. This process is described as a quantum tunneling effect.

That makes sense. So in fact there would be an imbalance.
Title: Re: Is Hawking radiation a red herring?
Post by: yor_on on 09/04/2015 16:13:51
This is so weird. Tried to answer giving a link, but got this when I tried to post?


Title: Re: Is Hawking radiation a red herring?
Post by: yor_on on 09/04/2015 16:22:06
Everything seems blacklisted suddenly?

Have to say that the version before this last update of SMF 2.0 | SMF © 2011, Simple Machines was more functional than what we have today. Try this http://www.thenakedscientists.com/forum/index.php?topic=36568.0
Title: Re: Is Hawking radiation a red herring?
Post by: PmbPhy on 09/04/2015 19:49:41
Quote from: jeffreyH
Hawking radiation is said to be due to a particle, anti-particle pair with one of them falling through the horizon while the other escapes.
Keep in mind that this refers pairs of virtual particles.

Quote from: jeffreyH
Presumably one will annihilate, the anti-particle, while the other continues to exist.
That is incorrect. The virtual particle pairs are created right outside the event horizon. One of the particles falls into the event horizon while the other escapes to infinity. The one that escapes to infinity has positive energy while the other has negative energy. The negative energy particle decreases the energy of the black hole and since E = mc2 it follows that the mass of the black hole decreases.
Title: Re: Is Hawking radiation a red herring?
Post by: jeffreyH on 09/04/2015 20:19:49
I tried to reply and got the blacklisted term message. It was just text. This is going to make the forum very unusable. What I said in that reply Pete was, that is why I dont discuss particle physics.
Title: Re: Is Hawking radiation a red herring?
Post by: jeffreyH on 09/04/2015 20:23:31
BTW It was the apostrophe in dont that prevented the post. So I presume it is database related.