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arXiv · 2106.01213

Spacetimes with continuous linear isotropies III: null rotations

M. A. H. MacCallum
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Abstract

It is shown that in many cases local null rotation invariance of the curvature and its first derivatives is sufficient to ensure there is an isometry group G with dimension at least 3 acting on (a neighbourhood of) the spacetime and containing a null rotation isotropy. Invariance of the second derivatives is additionally required to ensure this conclusion in Petrov type N Einstein spacetimes, spacetimes containing "pure radiation" (a Ricci tensor of Segre type [(11,2)]), and conformally flat spacetimes with a Ricci tensor of Segre type [1(11,1)] (a "tachyon fluid").

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M. A. H. MacCallum. 2021-06-02. Spacetimes with continuous linear isotropies III: null rotations. https://doi.org/10.1007/s10714-021-02869-1

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