This work concerns the invariant Lorentzian metrics on the Heisenberg Lie group of dimension three H3(R) and the bi-invariant metrics on the solvable Lie groups of dimension four. We start with the indecomposable Lie groups ...

The study object of the thesis is the spinor representation of a Lorentzian surface in the pseudo Euclidean space R2; 2: We prove that an isometric immersion of a simply connected Lorentzian surface in R2; 2 is equivalent ...

We analyze the infrared behavior of the two and four-point functions for the massless O(N) model in Lorentzian de Sitter spacetime, using the 1/N expansion. Our approach is based in the study of the Schwinger-Dyson equations ...

We construct linearized solutions to Vasiliev's four-dimensional higher spin gravity on warped AdS(3) x(xi)S(1) which is an Sp(2) x U(1) invariant non-rotating BTZ-like black hole with R-2 x T-2 topology. The background ...

We investigate how quantum dynamics affects the propagation of a scalar field in Lorentzian AdS. We work in momentum space, in which the propagator admits two spectral representations (denoted “conformal” and “momentum”) ...