Schwarzschild de Sitter and extremal surfaces

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We study extremal surfaces in the Schwarzschild de Sitter spacetime with real mass parameter.

• We find codim-2 timelike extremal surfaces stretching between the future and past boundaries that pass through the vicinity of the cosmological horizon in a certain limit.
• These are analogous to the surfaces in arXiv:1711.01107 [hep-th].
• We also find spacelike surfaces that never reach the future/past boundaries but stretch indefinitely through the extended Penrose diagram, passing through the vicinity of the cosmological and Schwarzschild horizons in a certain limit.