Zero point energy, hu?

JohnSmith · Post by **JohnSmith** » Sat Feb 21, 2009 1:30 pm

As I understand it, when virtual particles pairs are created, you get a 'normal' particle, and an antiparticle. If the antiparticle fell in more often than the normal one, that would let mass escape. I couldn't tell you why things don't average out, though.

Torulf2 · Post by **Torulf2** » Sat Feb 21, 2009 4:03 pm

I to understand it from Hawkings text, that the energy comes from the BH. The BH can disappear.

Otherwise Ithink it can be in this way.
Hawking radiation is dos not exist because the conservation of energy.
LHC may produce stabile BH and must be stopped.

I think Hawking is right and the CPE people wrong about this.

D Tibbets · Post by **D Tibbets** » Sat Feb 21, 2009 4:58 pm

JohnSmith wrote:As I understand it, when virtual particles pairs are created, you get a 'normal' particle, and an antiparticle. If the antiparticle fell in more often than the normal one, that would let mass escape. I couldn't tell you why things don't average out, though.

I don't think it makes any difference weather the particle or antiparticle is eaten by the black hole. Weather it retains it's condensed matter state or manages to anialate with a wandering particle/ antiparticle, the energy cannot escape through the event horizon.

As for the LHC producing devistating mini black holes, I don't think we have to worry. There are frequent very energetic cosmic ray hits in our upper atmosphere that are Much more powerful than anything the LHC can produce. If it was a problem, we would not be here to argue about it.

Dan Tibbets

KitemanSA · Post by **KitemanSA** » Sun Feb 22, 2009 3:28 am

Why should it matter which escapes? If any matter or antimatter escapes, it is energy escaping. Eventually, if the energy escaping exceeds the energy incoming, the BH evaporates. E=MC^2.

D Tibbets · Post by **D Tibbets** » Sun Feb 22, 2009 10:52 am

KitemanSA wrote:Why should it matter which escapes? If any matter or antimatter escapes, it is energy escaping. Eventually, if the energy escaping exceeds the energy incoming, the BH evaporates. E=MC^2.

Yes, but the energy escaping is from 1/2 of the pair of particles that seperate at the event horizon and that came from the vacuum energy, not the black hole. So, the black hole event horizon serves to seperate these 'virtual particles' long enough that they become real. One then feeds the black hole, and the other feeds the universe outside the black hole.

Actually, I'm wondering how much more complicated it is once realitivity is considered. The virtual particle pair are very close together initially, so very close to the event horizon. Only that 'escaping' particle that is traveling at an almost perfectly perpenticular direction and almost at the spped of light would eventually escape. Any traveling at a tangent would orbit or spiral back into the black hole (consider the limb darkening of a neutron star- those photons ejected towards you from the central face are seen, but those ejected from near the limbs towards you ar traveling at an acute angle to the surface, so at a certain point they fall back onto the neutron star due to the intense gravity which is not quite up to black hole stature. So, the black hole would seperate the vertual particle pair for long enough for them to become real, and then would eat not 50% of the resultant particles, but perhaps 99.99999... % of the particles.
From the perspective of the universe at large, a black hole would enlarge and eventually consume the entire universe, but due to time dialation, this might only become significant in the last few seconds of the unverse's life, And the density of the accumulating matter at the event horizon may creat enough 'pressure' that at the same time the universe explodes- ie an ossilating universe!

I'm sure I'm wrong somewhere (or many somewheres') in my reasoning, but makes for interesting speculation.

Dan Tibbets

Torulf2 · Post by **Torulf2** » Sun Feb 22, 2009 2:40 pm

One then feeds the black hole, and the other feeds the universe outside the black hole.

Hawking and all literature I hade read says that the hawking radiation makes BH to shrink.
You say it makes them to growth. Source please?

KitemanSA · Post by **KitemanSA** » Sun Feb 22, 2009 3:18 pm

D Tibbets wrote: Yes, but the energy escaping is from 1/2 of the pair of particles that seperate at the event horizon and that came from the vacuum energy, not the black hole. So, the black hole event horizon serves to seperate these 'virtual particles' long enough that they become real. One then feeds the black hole, and the other feeds the universe outside the black hole.

I am not a physicist, I don't even play one on TV, but I was under the impression that the particle pairs were created due to the gravitational energy from the BH. If the BH gravitational energy creates two particles, and one escapes...

tomclarke · Post by **tomclarke** » Sun Feb 22, 2009 4:21 pm

... conservation of energy=mass rules OK

dweigert · Post by **dweigert** » Sun Feb 22, 2009 4:59 pm

From what I was told, the particle pair that is spontaneously created, contains a "normal" particle, and a particle with negative mass. The negative mass particle is what falls into the BH. The normal one escapes and is seen as Hawking radiation, while the other causes the BH to shrink ever so slightly.

Dan

D Tibbets · Post by **D Tibbets** » Sun Feb 22, 2009 6:10 pm

That may be where I am wrong. I have been assuming that the particle pair came from the vacuum energy, in which virtual pairs are constantly croping up randomely, but so long as they mutually anialate each other faster than Plank(?) time the universe can ignore them (except for the Casimir effect, and as a convient mechanism for some other quantum machanic efftects). I have never seen a discription where the black hole creates local conditions that produce these virtual particle pairs. Certainly there is plenty of energy near the event horizen (providing there is some matter falling into the black hole) that could produce new matter, but again this energy is coming from the infalling matter, I not sure how this could become a net energy loser for the black hole. The virtual particles are a particle and an antiparticle (like an electron and a positron), both have the same mass. no such thing as a particle with negative mass exists that I know of (please ignor any ramifications of the currently concieved cosmological constant).

Finally, after looking into several cosmological books (for the layman) I realize that the black hole loses gravitational energy, not by creating the virtual particals, but by expending tidal energy in pulling them apart. This gravitational energy loss would have to be greater than the energy gained from eating one of the two particles. Hawking's theory may address this in detail, but the laymen discriptions I have seen gloss over it.

Dan Tibbets

kurt9 · Post by **kurt9** » Sun Feb 22, 2009 8:39 pm

My thought is that we sit back and watch if Jovian is about to produce any useful results in the next year or two. Their patent application details devices that can be fabricated by any MEMS foundry that can process at the 100 nanometer level or better, at a cost less than the $100K they got from the University of Colorado. So, at least they should have the financial resources to experimentally verify their theory.

This zero point energy stuff strikes me as flaky. However, Haisch seems like the most solid guy working in this area. If his experiment fails (like I think it will), he is likely to be quite open about it and will move on to other areas.

TallDave · Post by **TallDave** » Mon Feb 23, 2009 5:28 am

I have never seen a discription where the black hole creates local conditions that produce these virtual particle pairs.

The pairs are everywhere. According to Hawking's book, what happens at the event horizon of a black hole is that one virtual partner escapes, and one (its antipartner) doesn't. This gradually decreases the mass of the black hole until it evaporates. It's a very very very slow process; most black holes will be around long after all the stars have gone dark.

KitemanSA · Post by **KitemanSA** » Mon Feb 23, 2009 4:34 pm

TallDave wrote:It's a very very very slow process; most black holes will be around long after all the stars have gone dark.

IIRC, the process is inversly proportional to size, the bigger the slower. Smaller than a certain size, it evoporates quite quickly. This is his explanation for why there should not be any primordial mini-BHs lurking around. Also why the potential micro BHs made by LHC need not be feared. But...

Skipjack · Post by **Skipjack** » Mon Feb 23, 2009 8:42 pm

I might be wrong, but I always thought that people had a weird idea about the strength of a black hole.
They seem to think of it as this bottomless pitt that is infinitely strong, or something. Of course that is not the case.
Black holes (initially) do not have more mass than the sun they were created from. Only once they (slowly) get into contact with objects that increase their mass, they get bigger and gather more mass. Now this process takes a long time and requires a lot of mass to be there in the first place. If you created a micro black hole, it would not have more mass than the particles it was created from. So that would do exactly what? Nothing.
At least in my totally unphysicist opinion.

KitemanSA · Post by **KitemanSA** » Mon Feb 23, 2009 9:51 pm

Skipjack wrote:If you created a micro black hole, it would not have more mass than the particles it was created from. So that would do exactly what? Nothing.

There was at one time a thought that the big bang should have created a miriad BHs of all sizes, so mini and micro BHs should prevade the universe. One hypothesis had Tunguska being caused by a mini BH. However, no evidence was seen for the M&M BHs. The explanation could be, they never existed or it could be "they evaporate".
That leaves the LHC. If it makes micro BHs, and they DON'T evaporate, we could be in MAJOR trouble as they orbit thru the Earth, picking up mass and eventually swallow the planet completely. What fun! However, Hawkings says they evaporate. Hmmm...