Protons are always stable?

[alpha2cen]

Neutron and other particles life time is very short.

Why protons life time is long?

Any theory?

Are there any factor influence proton life time in the Universe?

Edited November 22, 2010 by alpha2cen

[alpha2cen]

Are there any proton decay signals in the cosmos?

 

Very short time decay ->

It would be very short and intense gamma-ray, I suppose.

Middle speed decay?

Any good data?

Edited November 24, 2010 by alpha2cen

[lemur]

I've never heard of electron-decay? How short is neutron life? What do they decay into, a proton and electron? When do electrons decay? What do they decay into?

[timo]

The keyword you are looking for is "proton decay". And to quote Wikipedia on that:

In particle physics, proton decay is a hypothetical form of radioactive decay in which the proton decays into lighter subatomic particles, such as a neutral pion and a positron. Proton decay has not been observed. There is currently no experimental evidence that proton decay occurs.

 

 

I've never heard of electron-decay? When do electrons decay? What do they decay into?

They don't.

How short is neutron life? What do they decay into, a proton and electron?

The lifetime of a free neutron is in the order of 12 minutes (or maybe so-is the half-life time; just look it up if you feel the exact number matters). The decay is into proton + electron + suitable neutrino (an anti-electronneutrino in this case).

Edited November 24, 2010 by timo

[alpha2cen]

Proton has one more up quark, and neutron has one more down quark.

But the difference is very big.

Are there any potential energy equations which describe elementary particle behavior?

Perhaps protons have very low potential energy.

[swansont]

Spontaneous decay requires the release of energy. If a particle decays, it needs to decay into something else, while conserving all of the quantities that are conserved, and the products must have a smaller mass. The decay chain has to end somewhere: the lightest particle (of that type)