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arXiv · hep-th/0203134

Penrose Limits of Orbifolds and Orientifolds

E. Floratos·A. Kehagias
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Abstract

We study the Penrose limit of various AdS_p X S^q orbifolds. The limiting spaces are waves with parallel rays and singular wave fronts. In particular, we consider the orbifolds AdS_3 X S^3/Γ, AdS_5 X S^5/Γand AdS_{4,7} X S^{7,4}/Γwhere Γacts on the sphere and/or the AdS factor. In the pp-wave limit, the wave fronts are the orbifolds C^2/Γ, C^4/Γand R XC^4/Γ, respectively. When desingularization is possible, we get asymptotically locally pp-wave backgrounds (ALpp). The Penrose limit of orientifolds are also discussed. In the AdS_5 X RP^5 case, the limiting singularity can be resolved by an Eguchi-Hanson gravitational instanton. The pp-wave limit of D3-branes near singularities in F-theory is also presented. Finally, we give the embedding of D-dimensional pp-waves in flat M^{2,D} space.

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E. Floratos, A. Kehagias. 2002-04-03. Penrose Limits of Orbifolds and Orientifolds. https://doi.org/10.1088/1126-6708%2F2002%2F07%2F031

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