anti-matter , what does this really mean ?

[north]

is not anti-matter really about " opposites "

 

if that is true wouldn't opposites attract ?

 

rather than destroy one-another ?

[Moontanman]

They do attract and when they come together they annihilate each other in a flash of gamma rays and other particles. I kilo of anti-matter and one kilo of matter if brought together would cause nearly a 50 megaton explosion.

 

http://en.wikipedia.org/wiki/Antimatter

 

The reaction of 1 kg of antimatter with 1 kg of matter would produce 1.8×1017 J (180 petajoules) of energy (by the mass-energy equivalence formula E = mc²), or the rough equivalent of 47 megatons of TNT. For comparison, Tsar Bomba, the largest nuclear weapon ever detonated, reacted an estimated yield of 50 Megatons, which required the use of hundreds of kilograms of fissile material (Uranium/Plutonium).

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To be completely honest there is a school of thought that says neutral anti atoms would repel atoms through gravitational repulsion but this isn't exactly what most think but it has never actually been shown one way or the other.

[north]

They do attract and when they come together they annihilate each other in a flash of gamma rays and other particles. I kilo of anti-matter and one kilo of matter if brought together would cause nearly a 50 megaton explosion.

 

http://en.wikipedia.org/wiki/Antimatter

 

this does not make sense

 

why would particles that are just opposite in polarity annialate each other ?

[swansont]

this does not make sense

 

why would particles that are just opposite in polarity annialate each other ?

 

Nature is under no obligation to make any sense. That's not an argument.

 

The particles annihilate because they are opposite in every characteristic that is conserved for matter (which we know because we create them in pairs).

[GDG]

Because, taken as a pair, all values except for mass and momentum can cancel out: the pair is thus equivalent to a pair of photons of the necessary energy. I suspect (without having done the calculation) that the reaction increases entropy, thus favoring photon formation.

[Moontanman]

So should we tell him about mirror matter?

 

http://en.wikipedia.org/wiki/Mirror_matter

[coke]

This I don't get about antimatter- its clear how electrons and positrons annhilate each other, and say an atom of matter would annhilate an atom of antimatter.

But say you just have a positron ray (thank cap'n for this idea) and you fire it at say a block of metal, what will happen?

Would the positrons annhilate the electrons and leave a bunch of protons, that with no chemical bonds would just seperate into plasma?

 

That's a good idea for a lightsaber!

[Moontanman]

I think thats the idea behind the "disrupter" on Star Trek, a beam of anti protons disrupts matter into it's constituent parts. Looks to me like a beam of positrons would do just as good.

[coke]

Yeah thats an interesting idea in itself...

Very good laser, would ionize any matter by contact into a plasma

 

I'll probably have to try that someday- strong laser making positrons, organized by several coils, and burning through anything...

 

I think in that context, the positrons would be even better at burning through things than the original laser...

[mr.mechanics]

but what could be a ' matter-ial' source of positron rays?

what kind of a 'matter-ial' gun would eject them?

even the air particles coming in contact of those rays would create very good heat!!

[coke]

matter source? well you're going to get antimatter anyways because positrons are antimatter!

 

light photons can be split up into positrons and electrons by a thin gold sheet, then positrons and electrons can be seperated by magnetic coils, see the link i gave above...natural radioactive decay is another option, but really its both less effective and requires exotic radioactive isotopes that have to be synthesized..