广义相对论与量子宇宙学

The late time response of vacuum black holes in General Relativity is notoriously governed by power law tails arising from the wave scattering off the curved spacetime geometry far from the black hole. While it is known that such tails are…

These are the extended lecture notes for a minicourse presented at the I S\~ao Paulo School on Gravitational Physics discussing the Bondi--Metzner--Sachs (BMS) group, the group of symmetries at null infinity on asymptotically flat…

We consider the possibility that gravity is mediated by "continuous spin" particles, i.e.~ massless particles whose invariant spin scale $\rho_g$ is non-zero. In this case, the primary helicity-2 modes of gravitational radiation on a…

Motivated by a recently discovered connection between the greybody factors of black holes and the ringdown signal, we investigate the greybody factors of ultracompact horizonless objects, also elucidating their connection to echoes. The…

On May 29, 2023, the LIGO Livingston observatory detected the gravitational-wave signal GW230529_181500 from the merger of a neutron star with a lower mass-gap compact object. Its long inspiral signal provides a unique opportunity to test…

A new set of fundamental commutation relations (CR) for quantum gravity is presented. The basic variables are the eight components of the unimodular part of the spatial dreibein and eight SL(3,R) generators which correspond to Klauder's…

The current network of gravitational wave detectors has already revealed hundreds of compact binary coalescences (CBCs), including binary neutron stars, binary black holes, and black hole-neutron star systems. As detector sensitivity…

We study the dynamics of the Bianchi~IX (Mixmaster) universe under classical polymerization and generalized uncertainty principle (GUP) deformation of the Poisson brackets. Starting from the Misner Hamiltonian, we derive the effective…

We study massless scalar, electromagnetic, and Dirac perturbations of asymptotically de Sitter black holes in generalized Proca theory. These geometries are especially interesting because the Proca sector generates both a primary-hair…

In this paper, we consider some causality violating solutions in the curvature-squared gravity in order to examine whether closed timelike curves (CTCs) are allowed in these models. These aspects are studied in terms of the G\"odel,…

Dynamical systems techniques are a powerful tool to analyse systems of ordinary differential equations, written in an appropriate form. For a given theory of gravity, the cosmological field equations typically lead to a system of ordinary…

We construct an effective-field-theory bridge from late-time scalar-tensor cosmology to black-hole ringdown observables. Starting from a cosmology-conditioned EFT posterior, we lift Jordan-frame FLRW data through a finite covariant jet,…

We develop a thermodynamic formulation of Cotton gravity in the Codazzi parametrization, providing a general framework in which the gravitational dynamics can be interpreted in terms of horizon thermodynamics. As paradigmatic examples, we…

GW240925 and GW250207 are two loud gravitational-wave signals from binary black hole coalescences observed with network signal-to-noise ratios $\sim 32$ and $\sim 69$, respectively, by the LIGO Hanford--LIGO Livingston--Virgo network.…

This study investigates a cosmological scenario within the f(Q,L_m) gravity framework to explore whether one geometric model can simultaneously describe the early and late-time accelerated epochs. Motivated by the recently proposed f(Q,L_m)…

The circuit dynamics constructed by traveling-wave parametric amplifiers (TWPA), using superconducting nonlinear asymmetric elements (SNAILs), are known to be approximately described by the Korteweg-de Vries (KdV) or modified KdV equations…

We study axial gravitational perturbations of the asymptotically flat Bardeen spacetime interpreted as a string-T-duality-inspired quantum-corrected Schwarzschild black hole. Starting from the anisotropic-fluid background, we derive the…

In this work, we investigate a cosmological model within modified teleparallel gravity using two functional forms of $f(T)$: a hybrid model $f(T)=e^{\gamma T}T^{\sigma}$ and a logarithmic model, in the context of a periodic cosmic evolution…

We develop a potential-independent cosmographic framework, in which cosmographic parameters are promoted to dynamical variables within a closed autonomous system. Although the cosmographic hierarchy is formally infinite, we achieve closure…

Fast surrogate models for expensive simulations are now essential across the sciences, yet they typically operate as black boxes. We present \texttt{GWAgent}, a large language model (LLM)-based workflow that constructs interpretable…