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arXiv · 2609.37427

Asymptotics of Killing horizons: A Characterization in de Sitter Spacetime

Carlos Peón-Nieto
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Abstract

We prove that (n + 1)-dimensional de Sitter spacetime is locally the unique $(Λ> 0)$-vacuum spacetime whose Killing horizons intersect the conformal boundary $\mathscr{I}$. The intersection occurs at the isolated essential zeros of the extension of the Killing vector field to $\mathscr{I}$. We then reconstruct all de Sitter Killing vector fields from their boundary value and obtain a characterization of those admitting a Killing horizon in terms of a conformal invariant $σ$: $σ<0$ characterizes non-degenerate bifurcate horizons, whereas $σ= 0$ yields degenerate non-bifurcate horizons. Finally, we derive an intrinsic, conformally invariant formula for the surface gravity of the horizons in de Sitter, $κ^2 = |σ|$.

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Carlos Peón-Nieto. 2026-09-29. Asymptotics of Killing horizons: A Characterization in de Sitter Spacetime. https://arxiv.org/abs/2609.37427

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