Assuming that the whole universe doesn't collapse upon itself, would matter eventually lose cohesion at an atomic level and cease to exist?

1 Answer
Feb 6, 2016

The ultimate fate of matters depends on whether protons decay.

Explanation:

Some theories of unification requires that protons decay. The decay mechanism is:
#p^+ rarrpi^0+e^-#
#pi^0 rarr 2 gamma#
Proton decay has not yet been observed and the lower limit for its half life is #10^32# years.

Neutrons, which are heavier than protons, have a half life in their free state of about 10 minutes. Neutrons decay into a proton and an electron. Bound neutrons have a half life in the order of that of protons.

So, if protons decay then ultimately all matter will decay.