Black hole thermodynamics

The aim of this lecture is to build a bridge between ordinary thermodynamics and black hole thermodynamics. To this end, we review the principles of general relativistic irreversible thermodynamics and derive a universal parameter thermodynamics for rotating fluids ("rotating bodies"). To extend the procedure to black holes, the black hole limit of the rigidly rotating disk of dust solution is discussed. It then turns out that the first law of black hole mechanics is just an extension of the Gibbs equation for the disk. Problems with the second law of black hole thermodynamics are discussed.