That is not dead which can eternal lie: the aestivation hypothesis for resolving The Fermi paradox 

If a civilization wants to maximize computation it appears rational to aestivate until the far future in order to exploit the low temperature en- vironment: this can produce a 1030 multiplier of achievable computation. This paper hence suggests the “aestivation hypothesis”: the reason we are not observing manifestations of alien civilizations is that they are currently (mostly) inactive, patiently waiting for future cosmic eras. This paper analyzes the assumptions going into the hypothesis and how physical law and observational evidence constrain the motivations of aliens compatible with the hypothesis.

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