Science a GoGo's Home Page Forums General Discussion General Science Discussion Forum Matter/anti-matter

Is there as much anti-matter in the universe as matter? If so, why do we not see as much anti-matter as matter?

There is a lot of antimatter. In fact our galaxy is currently creating an antimatter fountain that has been imaged.

http://antwrp.gsfc.nasa.gov/apod/ap970501.html

click on the various links under the image for more information on the subject.

Yes, so much even the Air Force is after it:

http://sfgate.com/cgi-bin/article.cgi?file=/c/a/2004/10/04/MNGM393GPK1.DTL

Erich

Erich there is this thing called "reality."

You should come in contact with it and see what it feels like.

There is not alot of antimatter. Physicists figure that at the time right after the big bang there was something like 1 000 000 particles of antimatter to 1 000 001 particles of matter. When antimatter and matter come into contact they are annihilated and form engergy in 1:1 ratios (ie 1 positron annihilates 1 electron). As a result of this annihilation taking place over the last 14 billion years and the one extra particle per million of matter over antimatter at the start of the universe there is an abundance of matter in the universe today, and a relative lack of antimatter.

Since I know this question will be asked: No one has come up with a suitable theory for why there was that extra particle of matter when the universe began.

Or how the partical, assuming it was 'a' particle, became active.

sp: 'particle'

The universe is all matter in substance. Events that create antimatter are notorious for their intense radiation emissions as said antimatter annihalates with surrounding ordinary matter.

An asymmetry in the structure of physics made the Big Bang generate an excess of matter over antimatter. The net bottom line is the universe - no resident antimatter and only transient when generated.

Potassium-40 has an inverse beta-decay channel. If you want some antimatter buy a bottle of KCl salt substitute. Hold it to a Geiger counter tube and listen to the crickets as 511 eV photons come shooting out from electron-positron annihalation events.

I'm not sure that its even known whether whole galaxies might not be anti-matter. There are slight differences in the properties of anti-matter vs matter, but I'm not sure if astronomers are able to measure such differences from distant galaxies to rule out that they might not all be anti-matter. Or all matter.

Some related info here:
http://physics.tamuk.edu/~hewett/ModPhy1/Unit1/SpecialRelativity/RelativeView/Energy/Antimatter/Annihilate/Annihilate.html

and here:
http://www.space.com/scienceastronomy/antimatter_sun_030929.html

Very interesting links. Thanks for posting them, and welcome to the forum.