Question about Matter / Anitmatter annihilation

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Woggles

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I was always wondering about this. I heard, read etc that matter and antimatter when in contact causes their annihilation. The dictionary say to reduce to utter ruin or nonexistence. The way I hear it when, describing matter/antimatter relationship as "nonexistence. My question is, how can this be? I never thought any thing actually can be nonexistence. Nothing is ever destroyed, just changes to a different state. As an example, a nuclear bomb. It changes from a solid material to an energy, i.e., radiation etc.
 
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origin

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Woggles":3l3obgmw said:
I was always wondering about this. I heard, read etc that matter and antimatter when in contact causes their annihilation. The dictionary say to reduce to utter ruin or nonexistence. The way I hear it when, describing matter/antimatter relationship as "nonexistence. My question is, how can this be? I never thought any thing actually can be nonexistence. Nothing is ever destroyed, just changes to a different state. As an example, a nuclear bomb. It changes from a solid material to an energy, i.e., radiation etc.

In the case of an electron (matter) and a positron (antimatter) they are completely annihilated, that is there is no more matter, however, the matter is converted 100% to energy (gama rays).
 
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Woggles

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ok thanks origin, now that clears that up! lol. Thanks always wonder about that.
 
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origin

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Woggles":19cp3aqy said:
ok thanks origin, now that clears that up! lol. Thanks always wonder about that.

No problem, glad to help clear it up!
 
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csmyth3025

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I've also wondered about particle/anti-particle annihilation. One thing perplexes me. In the case of - say - a helium nucleus and its antiparticle counterpart meeting up, the result is complete conversion to electromagnetic radiation (gamma rays). Does the strong nuclear force just "disappear" along with the matter? Is it some how converted to electromagnetic radiation, too?

Chris
 
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yevaud

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Excellent question!

No, there is no cancellation leading to a release of bound energies. They simply cancel each other out.
 
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centsworth_II

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csmyth3025":2xjoqdjz said:
...Does the strong nuclear force just "disappear" along with the matter? Is it some how converted to electromagnetic radiation, too?...
The strong nuclear force is carried by the gluons. In an anti-matter atom, the anti gluons would be destroyed by the gluons of a 'regular' atom just as the anti quarks are destroyed by quarks, and positrons by electrons. (The positron is the only anti particle with its own name.)
 
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yevaud

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You know, the more I look into this, the more it hares off into Quantum Chromodynamics. The best I *might* be able to say at this point is that a pion might be emitted. Or...not.
 
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Woggles

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Ok so if there is something left over from the annihilation, in this case energy and no mass, (or is there) would it be possible that this energy left over be Dark Energy? Or is it just cosmic background radiation?

From my reading on the blogs here, and other places, what we can see and detect is all that is left over from the BB and the matter/antimatter annihilation however in the begin there was substantial more matter. Taken from the view point that nothing really ever just disappears, just changes state, then wouldn't there be in our universe, everything from the begin.

Is it possible that the matter/antimatter annihilation create dark matter and or dark energy?
 
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csmyth3025

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centsworth_II":2eqydd4y said:
The strong nuclear force is carried by the gluons. In an anti-matter atom, the anti gluons would be destroyed by the gluons of a 'regular' atom just as the anti quarks are destroyed by quarks, and positrons by electrons. (The positron is the only anti particle with its own name.)

As I understand it a gluon is the named "particle" that's the force carrier for the strong nuclear force, just as the photon is the named "particle" that's the force carrier for the electromagnetic force. From your response I gather that there are gluons and anti-gluons that interact and mutually annihilate each other, their combined energies being emitted as photons (presumably gamma rays).

Extending this concept to all matter that is in motion and colliding with other (normal) matter - whether it be two planets colliding or two molecules jostling against each other - heat is always generated. This heat is radiated away in the form of electromagnetic radiation.

I suppose what I'm wondering is , after all the nuclear and gravitational energy of stars, galaxies, and galactic clusters is "used up", will the Universe be left with only thinly dispersed lumps of cold (near absolute zero) stable matter and electromagnetic radiation (photons)?

This thought leads me back to an item I read many years ago in Steven Weinberg's book "The First Three Minutes"(1977, Basic Books). After looking through the yellowed and somewhat tattered pages of my copy of his book I found his estimate that one of the conditions for the beginning state of the Universe is a baryon number of one per 1000 million photons. I wonder if this ratio is also the approximate condition for the end state of the Universe.

Chris
 
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yevaud

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That's just it though. A closer read of the cancellation of a Gluon field doesn't necessarily imply it emits a Photon. It depends, and how it does so is right smack in QCD. As I said, at times, it emits multiple Pions...or not. Depending.

Now two Quarks can annihilate and emit Photons, but not necessarily Gluons, a force-mediating particle.
 
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vogon13

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Not to make this even more complicated, but about 40% of the mass of proton (or neutron) (or the anti's) is attributed to the mass equivalency of the energy of motion of the constituent quarks and such. You may recall that E=MC^2 thingy now.

So if you had a kilogram of matter and a kilogram of anti-matter, and efficiently combined them, 1.2 kg of 'mass' will be zorched into gamma rays, and the energy already contained inside the masses in the form of kinetic energy of the 'innards' will be simultaneously released. Energy is energy, so you would not be able to discern which portion of the gammas was attributed to the actual mass and which to the considerable entrained energy incorporated inside the reactants.

While we may experience pure energy in our mortal forms, no one among us has yet experienced pure mass yet, just the 60/40 diluted crap we are stuck with.
 
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