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arXiv · 0806.2061

Singularities in geodesic surface congruence

Yong Seung Cho·Soon-Tae Hong
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Abstract

In the stringy cosmology, we investigate singularities in geodesic surface congruences for the time-like and null strings to yield the Raychaudhuri type equations possessing correction terms associated with the novel features owing to the strings. Assuming the stringy strong energy condition, we have a Hawking-Penrose type inequality equation. If the initial expansion is negative so that the congruence is converging, we show that the expansion must pass through the singularity within a proper time. We observe that the stringy strong energy conditions of both the time-like and null string congruences produce the same inequality equation.

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Yong Seung Cho, Soon-Tae Hong. 2008-06-12. Singularities in geodesic surface congruence. https://doi.org/10.1103/physrevd.78.067301

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