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Multipole Moments of Isolated Horizons

Abhay Ashtekar·Jonathan Engle·Tomasz Pawlowski·Chris Van Den Broeck
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Abstract

To every axi-symmetric isolated horizon we associate two sets of numbers, $M_n$ and $J_n$ with $n = 0, 1, 2, ...$, representing its mass and angular momentum multipoles. They provide a diffeomorphism invariant characterization of the horizon geometry. Physically, they can be thought of as the `source multipoles' of black holes in equilibrium. These structures have a variety of potential applications ranging from equations of motion of black holes and numerical relativity to quantum gravity.

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Abhay Ashtekar, Jonathan Engle, Tomasz Pawlowski, Chris Van Den Broeck. 2004-10-15. Multipole Moments of Isolated Horizons. https://doi.org/10.1088/0264-9381%2F21%2F11%2F003

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