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arXiv · hep-th/0211018

Tachyons in de Sitter space and analytical continuation from dS/CFT to AdS/CFT

M. Cadoni·P. Carta
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Abstract

We discuss analytic continuation from d-dimensional Lorentzian de Sitter (dS$_d$) to d-dimensional Lorentzian anti-de Sitter (AdS$_{d}$) spacetime. We show that AdS$_{d}$, with opposite signature of the metric, can be obtained as analytic continuation of a portion of dS$_d$. This implies that the dynamics of (positive square-mass) scalar particles in AdS$_{d}$ can be obtained from the dynamics of tachyons in dS$_d$. We discuss this correspondence both at the level of the solution of the field equations and of the Green functions. The AdS/CFT duality is obtained as analytic continuation of the dS/CFT duality.

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M. Cadoni, P. Carta. 2002-11-04. Tachyons in de Sitter space and analytical continuation from dS/CFT to AdS/CFT. https://doi.org/10.1142/s0217751x0401821x

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