collaborators

34 papers

hep-th2026

Dirac oscillator in a helically twisted spacetime with axial torsion

Matheus D. Moro, Fabiano M. Andrade, Faizuddin Ahmed +1

We investigate the Dirac oscillator in a helically twisted spacetime endowed with a uniform axial torsion. Starting from an orthonormal coframe, we compute the Levi--Civita spin co…

gr-qc2026

Particle dynamics and quasi-periodic oscillations of a Reissner--Nordström-like black hole in Kalb--Ramond gravity under an external magnetic test field

Faizuddin Ahmed, Ahmad Al-Badawi, Sardor Murodov +2

We investigate the dynamics of charged test particles and quasi-periodic oscillations around a Reissner--Nordström-like black hole in Kalb--Ramond (KR) gravity in the presence of…

gr-qc2026

ModMax black hole surrounded by perfect-fluid dark matter in Lorentz-violating Kalb-Ramond gravity

Fernando M. Belchior, Faizuddin Ahmed, Edilberto O. Silva

We investigate a ModMax black hole surrounded by perfect-fluid dark matter within the framework of Lorentz-violating Kalb-Ramond gravity. The model combines three physically distin…

gr-qc2026

Are There Closed Timelike Curves in -Gravity?

Faizuddin Ahmed, A. F. Santos

A modified gravitational model whose action is given by an arbitrary function of the Ricci scalar, the matter Lagrangian density, a scalar field, and its kinetic term is investigat…

gr-qc2026

ModMax-black hole surrounded by cloud of strings in Bumblebee gravity

Fernando M. Belchior, Allan R. P. Moreira, Abdelmalek Bouzenada +1

In this article, we investigate the optical, thermodynamic, and scattering properties of a ModMax black hole surrounded by a cloud of strings within the framework of Einstein-bumbl…

gr-qc2026

Transfer observables of rotating acoustic black holes from ray tracing: shadow centroid, redshift asymmetry and flux imbalance

Faizuddin Ahmed, Ahmad Al-Badawi, Fernando M. Belchior +1

We construct an impact-parameter-resolved transfer framework for null acoustic rays in the rotating draining-bathtub spacetime. The formalism separates the source-independent ray g…