'Most of us take it for granted that there are three dimensions, perhaps four if we count time. But for over 200 years, mathematicians and scientists have proposed further dimensions. In some standard versions of contemporary physics eleven dimensions are now proposed. But might the notion of additional dimensions be an empty idea that derails physics? Richard Feynman argued that proponents of extra dimensions "cook up explanations" for what we can't observe. And CERN researchers admit that no empirical evidence for extra dimensions has ever been, and more importantly perhaps could ever be, discovered.
Should we reject talk of higher dimensions as fantasy, good for sci-fi movies but not for theories of the universe? Would we be better to see extra dimensions as a mathematical tool rather than a description of reality? Or might multiple dimensions in fact describe the essential character of the world?
Nobel prize-winner Roger Penrose, philosopher of quantum mechanics Avshalom Elitzur, and theoretical physicist Marika Taylor, debate the possibility of multiple dimensions.