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arXiv · gr-qc/0603041

The Ernst equation and ergosurfaces

Piotr T. Chrusciel·Gert-Martin Greuel·Reinhard Meinel·Sebastian J. Szybka
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Abstract

We show that analytic solutions $\mcE$ of the Ernst equation with non-empty zero-level-set of $\Re \mcE$ lead to smooth ergosurfaces in space-time. In fact, the space-time metric is smooth near a "Ernst ergosurface" $E_f$ if and only if $\mcE$ is smooth near $E_f$ and does not have zeros of infinite order there.

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Piotr T. Chrusciel, Gert-Martin Greuel, Reinhard Meinel, Sebastian J. Szybka. 2006-06-04. The Ernst equation and ergosurfaces. https://doi.org/10.1088/0264-9381%2F23%2F13%2F007

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