Entropic N-bound and maximal mass conjecture violations in four-dimensional Taub-Bolt(NUT)-dS spacetimes

Abstract

We show that the class of four-dimensional Taub-Bolt(NUT) spacetimes with positive cosmological constant for some values of NUT charges are stable and have entropies that are greater than that of de Sitter spacetime, in violation of the entropic N-bound conjecture. We also show that the maximal mass conjecture, which states " any asymptotically dS spacetime with mass greater than dS has a cosmological singularity ", can be violated as well. Our calculation of conserved mass and entropy is based on an extension of the path integral formulation to asymptotically de Sitter spacetimes. © 2003 Elsevier B.V. All rights reserved.