arXiv subjects

Pelayo V. Calzada

Publications and source records attributed to Pelayo V. Calzada.

3 recordsLinked to original sources

arXiv2026

Homogeneous and Isotropic Linearized Gravity as a Caldeira--Leggett System

We show that the homogeneous and isotropic sector of linearized gravity coupled to arbitrary additional degrees of freedom takes the Caldeira-Leggett form, provided their action contains no metric time derivatives at second order in perturbations. These additional degrees of freedom constitute the model's harmonic reservoir. Eliminating them yields a generalized Langevin equation for the metric perturbation, with their influence condensed in the reservoir's spectral density. This equivalence also yields a natural setting for reduced quantization of the perturbation and stochastic gravitational dynamics. We analyze the resulting dynamics with Laplace methods, extending results presented in other open-system settings.

gr-qc↗

arXiv2026

Logarithmic corrections to black hole entropy from minimum-assumptions discretization

We introduce here a general model, under agnostic and minimum assumptions, to uniquely find the entropy area law with a corresponding fixed logarithmic correction term. In this approach, the horizon is discretized into generic Planck-scale cells representing coarse-grained indistinguishable geometric structures, and it is just the statistical combinatorial counting that determines the form of the entropy terms. We highlight the role of the assumptions and their comparison with known models providing fixed logarithmic contributions to the entropy.

gr-qc↗

arXiv2024

Static and spherically symmetric vacuum spacetimes with non-expanding principal null directions in $f(R)$ gravity

In this work we characterize all the static and spherically symmetric vacuum solutions in $f(R)$ gravity when the principal null directions of the Weyl tensor are non-expanding. In contrast to General Relativity, we show that the Nariai spacetime is not the only solution of this type when general $f(R)$ theories are considered. In particular, we find four different solutions for the non-constant Ricci scalar case, all of them corresponding to the same theory, given by $f(R) = r_0^{-1}\left\lvert R-3/r_0^2\right\rvert^{1/2}$, where $r_0$ is a non-null constant. Finally, we briefly present some geometric properties of these solutions.

gr-qc↗