Gravitational thermodynamics of causal diamonds
APA
Jacobson, T. (2019). Gravitational thermodynamics of causal diamonds. Perimeter Institute. https://pirsa.org/19050036
MLA
Jacobson, Ted. Gravitational thermodynamics of causal diamonds. Perimeter Institute, May. 21, 2019, https://pirsa.org/19050036
BibTex
@misc{ pirsa_PIRSA:19050036, doi = {10.48660/19050036}, url = {https://pirsa.org/19050036}, author = {Jacobson, Ted}, keywords = {Quantum Fields and Strings}, language = {en}, title = {Gravitational thermodynamics of causal diamonds}, publisher = {Perimeter Institute}, year = {2019}, month = {may}, note = {PIRSA:19050036 see, \url{https://pirsa.org}} }
Black hole (more generally, horizon) thermodynamics is a window into quantum gravity. Can horizon thermodynamics---and ultimately quantum gravity---be quasi-localized? A special case is the static patch of de Sitter spacetime, known since the work of Gibbons and Hawking to admit a thermodynamic equilibrium interpretation. It turns out this interpretation requires that a negative temperature is assigned to the state. I'll discuss this example, and its generalization to all causal diamonds in maximally symmetric spacetimes. This story includes a Smarr formula and first law of causal diamonds, analogous to those of black hole mechanics. I’ll connect this first law to the statement that generalized entropy in a small diamond is maximized in the vacuum at fixed volume.