Do you study quantum physics?
I only have secondary school physics from a useless teacher (~high school? Not sure) but I do know a little of this subject from fact-based science fiction and other materials.
As I understand it . . .
If the atom decays, which could theoretically happen at any time, the Geiger counter will detect it. This then activates a hammer, which releases the prussic acid, killing the cat.
Someone outside the box will not know what has happened, therefore it is unknown whether the atom has decayed, and therefore whether the cat is alive or dead.
This principle is based on the theory that something must be observed in order to happen, so it is neither the energy from the human eye (none) nor opening the box that kills the cat or shows it to be alive, it is the fact of being observed.
When there are multiple states something could be in, and it has not yet been observed, that is a superposition - it is in both states at once, until observed.
The theory then goes further, to say that everything not observed is in a superposition of all possible states, unless or until there exists some entity that can observe the entire universe at once, as well as any parallel universes or dimensions that may exist that could have an impact on this universe. Only then would everything be fixed into one state.
Anyway, that's how I understand it, I could be wrong and hopefully someone here has a better understanding than me.
