Do molecules have structure? The view from quantum physics

We learn from a young age that molecules have particular structures – these are the ball and stick models beloved of chemists: water is H2O and has a V-shape, methane is a pyramid, and diamonds are networks of tetrahedra. Molecular structure is used to explain reactivity, biological function, and even colour. However, if we attempt to develop a quantum physical account of structure from first principles, there is no apparent structure to be found. Chemists and philosophers of chemistry have named this puzzle ‘the problem of molecular structure’. In their prize-winning paper philosophers Vanessa Seifert and Alexander Franklin argued that this puzzle can be solved by any account that settles the long-standing quandary of Schrödinger’s cat! In this talk they’ll set out aspects of their research that illuminate the fundamental nature of the puzzling and bizarre quantum world.