Alessandro Podo: Naturalness of vanishing black-hole tides

jeudi 8 janv. 2026, 11:00 → 13:00 Europe/Paris

210/1-114 - Salle des Séminaires (IJCLab)

I will present a symmetry argument for the vanishing and non-renormalization of static Love numbers for spherically symmetric black holes at nonlinear order, in D=4 classical General Relativity. The symmetry is realized both in full GR and in the worldline EFT, allowing for a unified treatment. This clarifies the naturalness of vanishing static Love numbers in the worldline EFT when including non-linearities, and extends previous vanishing results to all nonlinear static tides. When extended to higher dimensional gravity, this also explains the pattern of vanishing and running static Love numbers of electric and tensor type, and predicts new results at the nonlinear order. I will also apply the same arguments to the tidal response of shift-symmetric scalar fields, predicting new zeros and unifying them with the no-hair theorem for shift-symmetric scalar fields (and its violations). If time permits, I will also comment on the extension of these results to backgrounds with electro-magnetic and gravito-magnetic charges. Based on joint work with Julio Parra-Martinez.