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arXiv · 0809.5033

Casimir energy in the gauge/gravity description of Bjorken flow?

K. Kajantie·Jorma Louko·T. Tahkokallio
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Abstract

In the AdS/CFT description of four-dimensional QCD matter undergoing Bjorken expansion, does the holographic energy-momentum tensor contain a Casimir-type contribution that should not be attributed to thermal matter? When the bulk isometry ansatz that yielded such a Casimir term for (1+1)-dimensional boundary matter is generalised to a four-dimensional boundary, we show that a Casimir term does not arise, owing to singularities in the five-dimensional bulk solution. The geometric reasons are traced to a difference between the isometries of AdS_3 and AdS_{d+1} for d>=3.

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K. Kajantie, Jorma Louko, T. Tahkokallio. 2009-01-04. Casimir energy in the gauge/gravity description of Bjorken flow?. https://doi.org/10.1103/physrevd.78.126012

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