Some exact solutions of colliding waves, black holes and their thermodynamical properties in Dilaton gravity

Abstract

We consider all possible theories in spherically symmetric Riemannian geometry in D-dimensions. We find solutions to such theories, in particular black hole solutions of the low energy limit of the string theory in Ddimensions and study their uniqueness. We find for the first time in literature, exact solutions of colliding Dilaton-Einstein-Maxwell Plane Waves. We investigate thermodynamical properties of four and five dimensional black hole solutions of toroidally compactified string theory. We find the explicit expression of the first law of black hole thermodynamics. We calculate the temperature T, angula,r velocity ÎÎ and the electromagnetic potentials on the horizon using two different methods. Collision of plane waves in dilaton gravity theories and low energy limit of string theory is considered. The formulation of the problem and some exact solutions are presented