Stephen Hawking Programme Last Week

[M4lcs67]

I saw a programme on Stephen Hawking last week (cannot remember which channel it was). Very good, however there was something in it that got me wondering. Back in the 70's he wrote a paper that at the time was supposed to be one of the greatest advanced in science. That matter could escape from black holes. I was led to believe that the gravitational pull around a black hole is that strong that even light cannot escape it. Once something has reached the event horizon it is doomed.

I hope I am making some sense. As the programme was on my wife and I discussed it and we were both of the same opinion that Hawkins paper flies in the face of everything that we knew.

Did anybody else watch the programme? Perhaps there is someone on SGL who is more knowledgeable about these things who could clarify it?

Thanks muchly. 

[JulianO]

Its probably hawking radiation you're thinking of. Its not quite stuff escaping from black holes... except it is in a way.

[Paul M]

My first encounter with the life of SH was in the late 70's. 

I read quite a bit about some of his work (at an accessible level!). I thought "A Brief History of Time" was a huge over-hype and have been wondering what all the fuss is about since.

Anyway, He postulated "Hawking Radiation" which was the apparent emission of particles by a black hole.

Quantum physics suggests that on the Plank scale, what we think of as empty space is in fact seething with "virtual particles" that flash into existence for fleetingly short periods. The exist in pairs of particle-antiparticle- keeping the mass/energy books balanced.

Now imagine a virtual particle pair in the vicinity of a black hole. Say the virtual anti-paricle gets drawn in and leaves its counter part behind. 

The anti particle annihilates its equivalent mass within the black hole making it lighter. The residual virtual particle now  exists in the real world. It's anti-buddy went and annihilated some one else. To the outsider this looks like the black hole is emitting particles and the black hole is losing mass.

It's a very slow process and not much of a threat to you average black hole.

I think...

[Christopher Davenport]

My first encounter with the life of SH was in the late 70's. 

I read quite a bit about some of his work (at an accessible level!). I thought "A Brief History of Time" was a huge over-hype and have been wondering what all the fuss is about since.

Anyway, He postulated "Hawking Radiation" which was the apparent emission of particles by a black hole.

Quantum physics suggests that on the Plank scale, what we think of as empty space is in fact seething with "virtual particles" that flash into existence for fleetingly short periods. The exist in pairs of particle-antiparticle- keeping the mass/energy books balanced.

Now imagine a virtual particle pair in the vicinity of a black hole. Say the virtual anti-paricle gets drawn in and leaves its counter part behind. 

The anti particle annihilates its equivalent mass within the black hole making it lighter. The residual virtual particle now  exists in the real world. It's anti-buddy went and annihilated some one else. To the outsider this looks like the black hole is emitting particles and the black hole is losing mass.

It's a very slow process and not much of a threat to you average black hole.

I think...

Nice explanation, this is how I understand the theory myself.

At a quantum level particles have a probability of existing in a certain space.

As they pop into existence then annihilate with there anti particles.

If this happens on the event horizon the two may appear on opposite sides of the line.

Now they can't annihilate with each other so they annihilate with another partner.

This should cause a black hole to glow with radiation. Not sure if this has been proven yet.

Anyways all very interesting, would be amazing to observe a black hole.

Dark Skies