Entropy of a Taub-bolt-AdS spacetime from an improved action principle

In this article the study of four-dimensional spaces with NUT charges and their ground states is continued. In particular, through the introduction of an improved action principle containing topological densities, it is shown that these spaces have simple and sound thermodynamical relations. As an example, the entropy of the Taub-bolt-AdS solution is computed in terms of a Noether charge.