Abstract
We investigate the thermodynamic properties of 3+1 dimensional black holes in asymptotically de Sitter spacetimes, conformally coupled to a real scalar field. We use a Euclidean action approach, where boundary value data is specified at a finite radius ‘cavity’ outside the black hole, working in the extended phase space where the cosmological constant is treated as a thermodynamic pressure. We examine the phase structure of these black holes through their free energy. For the MTZ subclass of solutions, we find Hawking-Page-like phase transitions from a black hole spacetime to thermal de Sitter with a scalar field. In the more general case, Hawking-Page-like phase transitions are also present, whose existence depends further on a particular cosmic censorship bound.
Highlights
Of studying strongly coupled systems nonperturbatively, and giving insights into the unitarity of black hole evaporation and the information problem
Upon taking the extended thermodynamic phase space into account, new phenomena emerge for charged de Sitter black holes, such as swallowtubes and analogues of the familiar Hawking-Page (HP), small-large, and reentrant phase transitions exhibited by AdS black holes [35,36,37]
We have studied the phase structure of a new class of asymptotically de Sitter black holes, conformally coupled to a real scalar field
Summary
The Euclidean action approach, which we employ here, provides a tool for studying gravitational thermodynamics when the spacetime under consideration does not admit a straightforward definition of temperature, as in those without global timelike Killing vector fields. Matter fields do not contribute to the path integral, allowing one to sum only over geometries This quantity can further be approximated by considering only the dominant contribution to the integral, which comes from metrics that are classical solutions to the equations of motion, namely those for which δIE[gcl] = 0. The variations above are done with all other parameters held fixed, possibly necessitating the inclusion of extra terms to account for the dependency of β on those parameters.3 This kind of approach has been used to study thermodynamic aspects of successively more exotic spacetimes ( with de Sitter asymptotics), such as neutral and charged de Sitter black holes [34, 35], Born-Infeld black holes [36], and Gauss-Bonnet black holes [37], demonstrating a wide variety of thermodynamic phenomena
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
