Research Outputs
Non-relativistic and ultra-relativistic expansions of three-dimensional spin-3 gravity theories
In this paper, we present novel and known non-relativistic and ultra-relativistic spin-3 algebras, by considering the Lie algebra expansion method. We start by applying the expansion procedure using different semigroups to the spin-3 extension of the AdS algebra, leading to spin-3 extensions of known non-relativistic and ultra-relativistic algebras. We then generalize the procedure considering an infinite-dimensional semigroup, which allows to obtain a spin-3 extension of two new infinite families of the Newton-Hooke type and AdS Carroll type. We also present the construction of the gravity theories based on the aforementioned algebras. In particular, the expansion method based on semigroups also allows to derive the (non-degenerate) invariant bilinear forms, ensuring the proper construction of the Chern-Simons gravity actions. Interestingly, in the vanishing cosmological constant limit we recover the spin-3 extensions of the infinite-dimensional Galilean and infinite-dimensional Carroll gravity theories.
Exact flavored black p-branes and self-gravitating instantons from toroidal black holes with Skyrme hair
In this paper, using the maximal embedding of SU(2) into SU(N) in the Euler angles parametrization, we construct a novel family of exact solutions of the Einstein SU(N)-Skyrme model. First, we present a hairy toroidal black hole in D ¼ 4 dimensions. This solution is asymptotically locally anti–de Sitter and is characterized by discrete hair parameters. Then, we perform a dimensional extension of the black hole to obtain black p-branes as solutions of the Einstein SU(N)-nonlinear sigma model in D ≥ 5 dimensions. These are homogeneous and topologically protected. Finally we show that, through a Wick rotation of the toroidal black hole, one can construct an exact self-gravitating instanton. The role that the flavor number N plays in the geometry and thermodynamics of these configurations is also discussed.