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The past light-come of C 2 at τ = −1 and the past light cone of C 1 between τ and τ + δτ for τ > r − 1.  

The past light-come of C 2 at τ = −1 and the past light cone of C 1 between τ and τ + δτ for τ > r − 1.  

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In a metastable de Sitter space any object has a finite life expectancy beyond which it undergoes vacuum decay. However, by spreading into different parts of the universe which will fall out of causal contact of each other in future, a civilization can increase its collective life expectancy, defined as the average time after which the last settlem...

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Citations

... the number of membranes that hit an observer per unit time. We will now do so by geometric means, as in [37]. ...
... This equation gives the probability that a bubble which was born at conformal time τ 0 actually makes it to conformal time τ (see [37]). In terms of proper time, we have ...
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... The work[30] discusses these points in great detail, including implications for holography. Related lifetimes for dS or general FLRW spacetimes are also discussed in[31]. We thank Ashoke Sen for brining these subtleties and references to our attention.5 ...
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... [7][8][9] ). When discussing the future of our Universe and illustrating how a continuing accelerated expansion would look like, one again appeals to "future cosmology" in both research [10][11][12][13] and popular science articles. [14][15][16][17] A lot of research and popular literature has been devoted to the subject of habitable planets, where one often "depicts" how life would look like with different kinds of suns 18 including "life in the early Universe". ...
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