arXiv subjects

Martin Enriquez-Rojo

Publications and source records attributed to Martin Enriquez-Rojo.

7 recordsLinked to original sources

arXiv2023

Asymptotic dynamics and charges for FLRW spacetimes

We investigate the asymptotia of decelerating and spatially flat FLRW spacetimes at future null infinity. We find that the asymptotic algebra of diffeomorphisms can be enlarged to the recently discovered Weyl-BMS algebra for asymptotically flat spacetimes by relaxing the boundary conditions. This algebra remains undeformed in the cosmological setting contrary to previous extensions of the BMS algebra. We then study the equations of motion for asymptotically FLRW spacetimes with finite fluxes and show that the dynamics is fully constrained by the energy-momentum tensor of the source. Finally, we propose an expression for the charges that are associated with the cosmological supertranslations and whose evolution equation features a novel contribution arising from the Hubble-Lemaître flow.

gr-qc↗

arXiv2022

Asymptotic symmetries and memories of gauge theories in FLRW spacetimes

In this paper, we investigate the asymptotic structure of gauge theories in decelerating and spatially flat Friedmann-Lemaître-Robertson-Walker universes. Firstly, we thoroughly explore the asymptotic symmetries of electrodynamics in this background, which reveals a major inconsistency already present in the flat case. Taking advantage of this treatment, we derive the associated memory effects, discussing their regime of validity and differences with respect to their flat counterparts. Next, we extend our analysis to non-Abelian Yang-Mills, coupling it dynamically and simultaneously to a Dirac spinor and a complex scalar field. Within this novel setting, we examine the possibility of constructing Poisson superbrackets based on the covariant phase space formalism.

hep-th↗

arXiv2022

Boundary Heisenberg Algebras and Their Deformations

We investigate the deformations and rigidity of boundary Heisenberg-like algebras. In particular, we focus on the Heisenberg and $\text{Heisenberg}\oplus\mathfrak{witt}$ algebras which arise as symmetry algebras in three-dimensional gravity theories. As a result of the deformation procedure we find a large class of algebras. While some of these algebras are new, some of them have already been obtained as asymptotic and boundary symmetry algebras, supporting the idea that symmetry algebras associated to diverse boundary conditions and spacetime loci are algebraically interconnected through deformation of algebras. The deformation/contraction relationships between the new algebras are investigated. In addition, it is also shown that the deformation procedure reaches new algebras inaccessible to the Sugawara construction. As a byproduct of our analysis, we obtain that $\text{Heisenberg}\oplus\mathfrak{witt}$ and the asymptotic symmetry algebra Weyl-$\mathfrak{bms}_3$ are not connected via single deformation but in a more subtle way.

hep-th↗

arXiv2021

On deformations and extensions of $\text{Diff}(S^2)$

We investigate the algebra of vector fields on the sphere. First, we find that linear deformations of this algebra are obstructed under reasonable conditions. In particular, we show that $hs[λ]$, the one-parameter deformation of the algebra of area-preserving vector fields, does not extend to the entire algebra. Next, we study some non-central extensions through the embedding of $\mathfrak{v}\mathfrak{e}\mathfrak{c}\mathfrak{t}(S^2)$ into $\mathfrak{v}\mathfrak{e}\mathfrak{c}\mathfrak{t}(\mathbb{C}^*)$. For the latter, we discuss a three parameter family of non-central extensions which contains the symmetry algebra of asymptotically flat and asymptotically Friedmann spacetimes at future null infinity, admitting a simple free field realization.

hep-th↗

arXiv2021

Asymptotic symmetries in spatially flat FRW

We perform an off-shell treatment of asymptotically decelerating spatially flat FRW spacetimes at future null infinity. We obtain supertranslation and superrotation-like asymptotic diffeomorphisms which are consistent with the global symmetries of FRW and we compute how the asymptotic data is transformed under them. Further, we study in detail the effect of these diffeomorphisms on some simple backgrounds including unperturbed FRW and Sultana-Dyer black hole. In particular, we investigate how these transformations act on several cosmologically perturbed backgrounds.

hep-th↗

arXiv2021

Holography and black holes in asymptotically flat FLRW

In this paper, we extend the treatment of asymptotically decelerating spatially flat FLRW spacetimes initiated in [1]. We show that a certain class of those metrics is ruled by the asymptotic algebra $\mathfrak{b}\mathfrak{m}\mathfrak{s}_s$, which belongs to a one-parameter family of deformations of $\mathfrak{b}\mathfrak{m}\mathfrak{s}$. Furthermore, we enlarge our ansatz to include $\text{Diff}(S^2)$ transformations whose asymptotic algebra $\mathfrak{g}\mathfrak{b}\mathfrak{m}\mathfrak{s}_s$ is a one parameter deformation of $\mathfrak{g}\mathfrak{b}\mathfrak{m}\mathfrak{s}$. Therefore, the holographic algebras $\mathfrak{b}\mathfrak{m}\mathfrak{s}_s$ and $\mathfrak{g}\mathfrak{b}\mathfrak{m}\mathfrak{s}_s$ in FLRW can be related to their flat counterparts through a cosmological holographic flow. Finally, we introduce a logarithmic ansatz in order to account for cosmological black holes, which does not generally satisfy the peeling property but preserves the asymptotic algebra.

gr-qc↗

arXiv2020

Swampland conjectures for type IIB orientifolds with closed-string U(1)s

We study the weak gravity conjecture, the swampland distance conjecture and the emergence proposal for $\mathcal{N}=1$ orientifold compactifications of type IIB string theory with O3-/O7-planes. We allow for orientifold projections with $h^{2,1}_+\neq 0$ which gives rise to closed-string $U(1)$ gauge fields, and our findings show that certain structures present for $\mathcal N=2$ compactifications are not present for $\mathcal N=1$. In particular, assumptions about stability have to be relaxed and we encounter an ambiguity for the emergence of gauge symmetries associated with the $h^{2,1}_+$ sector.

hep-th↗