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arXiv · 2503.24265

Charges, complex structures, and perturbations of instantons

Lars Andersson·Bernardo Araneda
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Abstract

Hermitian non-K\"ahler Einstein 4-manifolds have a quasi-locally conserved charge associated to spin-lowering via Killing spinors, and corresponding to a parameter of the moduli space. This charge is evaluated for all explicitly known examples of gravitational instantons. Generic gravitational perturbations are shown to admit a closed 2-form that measures the perturbation to this charge, generalizing previous Lorentzian results on the linearized mass of perturbed Kerr black holes.

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Lars Andersson, Bernardo Araneda. 2025-03-31. Charges, complex structures, and perturbations of instantons. https://arxiv.org/abs/2503.24265

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