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arXiv · 0906.3003

On the gravitational polarizability of black holes

Thibault Damour·Orchidea Maria Lecian
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Abstract

The gravitational polarizability properties of black holes are compared and contrasted with their electromagnetic polarizability properties. The "shape" or "height" multipolar Love numbers h_l of a black hole are defined and computed. They are then compared to their electromagnetic analogs h_l^{EM}. The Love numbers h_l give the height of the l-th multipolar "tidal bulge" raised on the horizon of a black hole by faraway masses. We also discuss the shape of the tidal bulge raised by a test mass m, in the limit where m gets very close to the horizon.

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Thibault Damour, Orchidea Maria Lecian. 2009-06-16. On the gravitational polarizability of black holes. https://doi.org/10.1103/physrevd.80.044017

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