Is there any reason the Universe must have a wave function?

C Rob

I believe it does, but I'm having a debate with someone and I'm trying to prove why the universe must have a wave function. I was under impression the best equations for describing our universe involve it having it's own wave but he's asserting it doesn't need one. Can anyone help me?

cmos

An isolated physical system will have a wavefunction. So particle-in-a-box has a wavefunction. Now make it two-particles-in-a-box. The wavefunction of that system is distinct from that of the first system. Same goes for many-particles-a-box; distinct wavefunction from that of the previous two systems. Now let our isolated system be the universe. Therefore, by the same reasoning, the universe has a wavefunction.

Disclaimer: I feel that decoherence makes the above argument invalid for macroscopic systems. Maybe someone else can shed some more light on this.

vanesch

That depends on whether you think quantum mechanics is applicable to the universe or not.

George Jones

The title of this thread is that same as the title of a thread in the Beyond the Standard Model forum. I have locked the thread here, and I have copied the posts in the thread here into the thread there. Any replies should be made there.