0 temperture?

[pivoxa15]

If the universe consisted only of He atoms and all of them are in the ground state, does it imply this universe has 0 or close to 0 kelvin? It is only the deexcitation of the outer electron emitting a photon which can produce any significantly measurable heat in the universe?

[Gib Z]

Maybe close to 0 kelvin, but never precisely. Laws of Thermodynamics and Heisenbergs Uncertainty Principle tell me that.

Of close we would have to take other things into account if we want more detailed approach, such as how a Universe Could only consist of He atoms when Hydrogen atoms are needed to form those. And that there should be other energy from certain interactions.

[pivoxa15]

I am proposing a hypothetical universe which consists of only He atoms. However I like the physics between atoms to be the same as our universe.