On the Concept of Law in Physics

I discuss the main features of the concept of law in physics. Fundamental laws from Newtonian mechanics to general relativity are reviewed. I end with an outlook on the new form of laws in the emerging theory of quantum gravity.Comment: 10 pages, to appear in the Proceedings of the conference "The concept of law in science", Heidelberg, 4-5 June 201

Quantum Cosmology and the Arrow of Time

Although most fundamental laws are invariant under time reversal, experience exhibits the presence of irreversible phenomena -- the arrows of time. Their origin lies in cosmology, and I argue that only quantum cosmology can provide the appropriate formal framework. After briefly reviewing the formalism, I discuss how a simple and natural boundary condition can lead to the observed arrows of time. This yields at the same time interesting consequences for black holes.Comment: 10 pages, contribution to the Proceedings of the conference DICE2004, Piombino, Italy, September 200