Build up of the Universe

[reportmonkey]

Does every atomic structure have a half life? Is everything in a state of decay? For example what would be the ultimate state of decay...energy?

[fo3nix]

from quantum mechanics, everything is wanting to decay. some things don't seem to, but they do want to.

ultimate state: unknown (the honest answer). many theories. perhaps they all decay back into little strings?

[jake-the-peg]

You have to be a bit careful how you phrase the question.

Not everything is an atom by a long way.

It is believed that protons may be unstable with a half life of around 10 to the power 32 years but determining this is obviously very difficult.

If true however this would violate the conservation of baryon number. Conservation laws are very important in physics because they are linked to so called symmetries.

The last time we saw symmetry breaking was in parity where "left-right handedness" was not conserved in a particular nuclear decay - this lead to the conception and discovery of anti-matter.

As for the ultimate state, well that's rather difficult to speculate on when you're dealing with timescales billions and billions of times longer than the existing history of the universe - A bit like a mayfly tring to conceive of the next millenia

[Clanad]

 

In relation to your second question, it is and is known as entropy and is the Second Law of Thermodynamics...

Entropy definition: Energy spontaneously disperses from being localized to becoming spread out if it is not hindered.