What is the Universe?

There still appears to be no clear answer to this question, and, to be honest, it's becoming a little embarrassing. The possibilities touted so far include:




• A concentric set of crystal spheres
• A clockwork mechanism
• A reversible/irreversible heat engine
• A billiard ball system
• A bubble
• A work of art
• A living organism
• The mind of a person
• A smooth geometry containing a fluid (general relativistic cosmology)
• A sponge
• A computer
• A computer program
• A wave function (quantum cosmology)
• A fluctuating foam (quantum gravity)
• An ecosystem
• A fractal
• A mathematical structure
• A musical symphony of vibrating strings in 11 dimensions (superstring theory)

Take your pick. You're unlikely to be proven wrong.