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arXiv · gr-qc/0312086

The ultrarelativistic limit of 2D dilaton gravity and its energy momentum tensor

H. Balasin·D. Grumiller
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Abstract

The ultrarelativistic limit of twodimensional dilaton gravity is presented and its associated (anti-)selfdual energy momentum tensor is derived. It is localized on a null line, although the line element remains twice differentiable. Relations to the Aichelburg-Sexl spacetime and constant dilaton vacua are pointed out. Geodesics are found to be smooth for minimally coupled test particles but non-smooth -- with a finite jump in the acceleration -- for test particles coupled non-minimally to the dilaton. Quantization on boosted backgrounds is discussed; no anomalous trace of the energy momentum tensor arises and the 1-loop flux component can be adjusted to be equal to the classical flux of the shock wave.

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H. Balasin, D. Grumiller. 2004-04-19. The ultrarelativistic limit of 2D dilaton gravity and its energy momentum tensor. https://doi.org/10.1088/0264-9381%2F21%2F12%2F006

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