QUANTUM BOUNDS FOR GRAVITATIONAL DE SITTER ENTROPY AND THE CARDY–VERLINDE FORMULA

Abstract
We analyze different types of quantum corrections to the Cardy–Verlinde entropy formula in a Friedmann–Robertson–Walker universe and in an (anti)-de Sitter space. In all cases we show that quantum corrections can be represented by an effective cosmological constant which is then used to redefine the parameters entering the Cardy–Verlinde formula so that it becomes valid also with quantum corrections, a fact that we interpret as a further indication of its universality. A proposed relation between Cardy–Verlinde formula and the ADM Hamiltonian constraint is given.