The aestivation hypothesis, is a hypothesized solution to the Fermi paradox conceived in 2017 by Anders Sandberg, Stuart Armstrong and Milan M. Ćirković. The hypothesis, published on April 27, 2017, suggests that advanced alien civilizations may be storing energy and aestivating (hibernating in times of heat instead of cold), until the universe cools to better make use of the stored energy to perform tasks.
As the universe cools, the potential work producible by stored energy can increase by a multiplier of 1030. If the goal of an advanced civilization is to maximize the number of calculations done, to generate information processing for tasks like mass-producing simulations, then aestivation would be purposeful to achieve this end.
Advanced alien civilizations may have other intentions. If the intent is creating large amounts of "happiness", then energy resources may be used to generate perfect computer simulations of "the maximal number of maximally happy minds". If the intent is knowledge, resources may be focused on information storage. Such civilizations may go through a time of exploration and then remain dormant until the conditions of the universe are more energetically favorable to best achieve their objectives.
The theory has been disputed by a subsequent paper by Charles H. Bennett, Robin Hanson and Jess Riedel, which claims that the notion that more computations could be performed later in the universe's history is based on a misunderstanding of the physics of computation.
- Sandberg, Anders; Armstrong, Stuart; Ćirković, Milan M. (27 April 2017). "That is not dead which can eternal lie: the aestivation hypothesis for resolving Fermi's paradox". arXiv:1705.03394 [physics.pop-ph].
- Dvorsky, George (31 May 2017). "Hibernating Aliens Could Explain the Great Silence". Gizmodo. Retrieved 29 March 2018.
- Tangermann, Victor (1 December 2017). "Where is alien life? Six of the top theories". Futurism. Retrieved 29 March 2018.
- Bennett, Charles; Hanson, Robin; Riedel, Jess (18 February 2019). "Comment on 'The aestivation hypothesis for resolving Fermi's paradox'". arXiv:1902.06730 [physics.pop-ph].