# Tag Info

## About anti-de-sitter-spacetime

Anti-de-Sitter (AdS) spacetime is a spacetime with a constant negative Ricci Scalar. It has a pseudo-metric:

$${\text{d}}{s^2} = \sum\limits_{i = 1}^p {{\text{d}}x_i^2 - \sum\limits_{j = 1}^{q + 1} {{\text{d}}t_j^2} }$$

AdS Spacetime has played an important role in the correspondence.