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antimatter at c

 
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Jul5-09, 11:43 AM   #18
 
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antimatter at c


Quote by crapola77 View Post
in steven hawkings new series on the sci channel aptly named "master of the universe" he says "in empty space this energy takes the form of pairs of subatomic particles that emerge out the void, exist for less than a nano second and then annihilate each other. so the idea is, out of nothing if you like, a pair of particles is created and then exists for a short time and then annihilates and that's happening through out space" how is this possible? and why doesn't this light up the universe with the resulting gamma radiation?
This is the "free energy" nonsense that many crackpot are trying to push. If there is THAT much pair production out of empty space, then our universe would have been opaque, and we would not have to go to such a difficult extent to detect the Casimir forces.

Quote by crapola77 View Post
because i was under the impression that annihilation created space, i assumed that this explained the expansion of space
Your impression is incorrect.

Zz.
Jul5-09, 12:08 PM   #19
 
so are you saying this isn't proven, by what mechanism do they explain how matter and antimatter are being created out of nothing? the validity of this in mind seams easy to test, wheres all the radiation from them?
Jul5-09, 12:38 PM   #20
 
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Quote by crapola77 View Post
so are you saying this isn't proven, by what mechanism do they explain how matter and antimatter are being created out of nothing? the validity of this in mind seams easy to test, wheres all the radiation from them?
What isn't "proven"?

Vacuum fluctuation has been shown to be valid, per the Casimir effect. However, the speculation that one can harness significant energy, the way you are equating it with nuclear energy, so far has been shown to be a fallacy.

Zz.
Jul5-09, 01:14 PM   #21
 
Quote by crapola77 View Post
because i was under the impression that annihilation created space, i assumed that this explained the expansion of space
Hi 77,

I have not heard that before, but it is an interesting hypothesis! If particles pop into existence and then annihilate each other, becoming gamma ray radiation, then we have something for nothing. But that is what Allan Guth says we have: "The universe is the ultimate free lunch." The same would be true if the annihilation became more space instead of gamma rays. In one case we have light energy, in the other case we have dark energy.

-S
Jul5-09, 02:50 PM   #22
 
Fermilab usually has over 1012 antiprotons (about 0.2 microCoulombs) circulating in the 6,280-meter-circumference Tevatron (beam tube diameter about 7.5 cm) at about 980 GeV (gamma = 1044, beta = 0.999 999 5). Each annihilating antiproton at rest would release about 3 x 10-10 joules, so 1012 annihilating antiprotons will release about 300 joules of energy (note: TNT has about 4000 joules per gram). Most of the 980-GeV antiproton energy is kinetic, not in its annihilation mass.
Although most of the annihilation energy initially produces pions and other mesons, eventually it all converts to ionization energy (heat) plus (aniti)neutrinos.
See http://www.fnal.gov/pub/about/experi...ndex.html#list
Jul5-09, 03:36 PM   #23
 
Quote by StandardsGuy View Post
If particles pop into existence and then annihilate each other, becoming gamma ray radiation...
Wait. When did we say this?

Virtual particles, created from vacuum then recombining again is not the same thing as matter and antimatter. This is mixing two separate phenomena.
Jul5-09, 03:39 PM   #24
 
Quote by crapola77 View Post
and also


but has there ever been any testing done on antimatter in the form of breaking the bonds of the nucleus to release energy as with the atomic bomb. does anti atom have a strong force?
An atom of anti-matter is identical to an atom of matter is every way except the charges on its components. In anti-matter, the anti-proton(s) have a negative charge and the anti-electron(s) have a positive charge.
Jul5-09, 10:06 PM   #25
 
When the particles "pop into existence", they still have to obey e=mc^2 - it takes energy to create this mass. When they annihilate each other, they create the gamma radiation, which has exactly the same energy as it took to create the two particles. All that is happening is that for a very brief moment energy is turned into matter and then back into energy.
Jul5-09, 10:21 PM   #26
 
Quote by Airman View Post
When the particles "pop into existence", they still have to obey e=mc^2 - it takes energy to create this mass. When they annihilate each other, they create the gamma radiation, which has exactly the same energy as it took to create the two particles. All that is happening is that for a very brief moment energy is turned into matter and then back into energy.
People have already pointed out that the particles aren't real. Doesn't your assumption predict that empty space consists of photons and antimatter and matter pairs. This is not 'empty' space. This is electrons and positrons.. real electrons and positrons. From what I understand, empty space is called empty for a reason... nothing is there.. including photons.

The particles in vacuum fluctuations are virtual. Do they anhilate to form photons? I don't think so. Maybe virtual photons? I'm not sure. If someone knows that, that would help.
Jul6-09, 07:51 AM   #27
 
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There are already numerous threads discussing virtual particles here on PF. Please find those and direct your questions about virtual particles there. If not, this thread will seriously go off-topic and will be closed.

Zz.
Jul7-09, 11:12 PM   #28
 
Quote by ZapperZ View Post
In [itex]E = mc^2[/itex], you'll note that that "m" doesn't discriminate between matter and antimatter.
Zz.

yes is the equation technically not [itex]E= +- mc^2[/itex] , the minus sign giving flame for the discovery of antimatter? Basically the equation works both ways.
Jul8-09, 12:20 AM   #29
 
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Both matter and antimatter have positive mass, as far as we know.
Jan24-11, 11:13 AM   #30
 
is it possible to convert pure energy into matter.I mean E=m^c .Does it exist any way to produce "mass"
Jan24-11, 06:24 PM   #31
 
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Quote by cosmos seeker View Post
is it possible to convert pure energy into matter.I mean E=m^c .Does it exist any way to produce "mass"
I believe that particle colliders do this. Colliding high energy (IE Fast Moving) particles together can result in many particles created. However it is not in a very controlled way and there really isn't reason to try to use this for anything other than research currently. Keep in mind that alot of the particles created are unstable and will decay into lighter particles or photons very quickly after formation.
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