arXiv subjects

Yun-Ten Chin

Publications and source records attributed to Yun-Ten Chin.

2 recordsLinked to original sources

arXiv2026

Magnetising de Sitter and Anti-de Sitter spacetimes

We attempt to magnetise the de Sitter (dS) and Anti-de Sitter (AdS) spacetimes in spherical symmetry. First, the weak field case is considered where Maxwell's equation is solved to find magnetic fields in fixed dS/AdS backgrounds. For strong magnetic fields we consider Einstein-Maxwell gravity with a gravitating fluid source. With gravitational backreaction of the magnetic field taken into account, the strong fields deform the dS/AdS spacetime, resulting in a dS/AdS-type analogue of the Melvin magnetic universe. This solution is obtained via a Harrison-like transformation, along with appropriate transformations of the fluid energy and pressures. Some of its physical and geometrical properties of the solution are studied.

gr-qc↗

arXiv2025

Properties of the magnetic universe with positive cosmological constant

The properties of the Melvin-type spacetime with a positive cosmological constant $Λ$ in $d$-dimensional Einstein--Maxwell gravity is studied. The solution is parametrised in terms of the `de Sitter radius' $\ell\proptoΛ^{-1/2}$ and the magnetic field parameter $β$, and they are warped products of the form $\mathbb{R}^{1,d-3}\times S^2$, where $\mathbb{R}^{1,d-3}$ is the $(d-2)$-dimensional Minkowski spacetime and $S^2$ is topologically a two-sphere which contains a conical singularity, whose nature depends on the product $β\ell$. In the limit $\ell\rightarrow\infty$, the $S^2$ decompactifies and the $d$-dimensional Melvin universe is recovered. The Freund--Rubin-type flux compactification model is shown to be another particular limit of this solution. We also calculate the flux and geodesics in this spacetime.

gr-qc↗