Life versus dark energy: How an advanced civilization could resist the accelerating expansion of the universe

Abstract

The presence of dark energy in our universe is causing space to expand at an accelerating rate. As a result, over the next approximately 100 billion years, all stars residing beyond the Local Group will fall beyond the cosmic horizon and become not only unobservable, but entirely inaccessible, thus limiting how much energy could one day be extracted from them. Here, we consider the likely response of a highly advanced civilization to this situation. In particular, we argue that in order to maximize its access to useable energy, a sufficiently advanced civilization would chose to expand rapidly outward, build Dyson Spheres or similar structures around encountered stars, and use the energy that is harnessed to accelerate those stars away from the approaching horizon and toward the center of the civilization. We find that such efforts will be most effective for stars with masses in the range of M ∼ (0.2 − 1)M , and could lead to the harvesting of stars within a region extending out to several tens of Mpc in radius, potentially increasing the total amount of energy that is available to a future civilization by a factor of several thousand. We also discuss the observable signatures of a civilization elsewhere in the universe that is currently in this state of stellar harvesting.

SETI: the argument for artefact searches

“…Hooper (2018) has noted that truly advanced societies would want to harvest other star systems to increase their energy supply. Cosmic expansion (and the more recent acceleration of that expansion) causes the stars of other galaxies to relentlessly retreat.…”

Conspiratorial cosmology. II. The anthropogenic principle

“…any more, and if we do not want to fall into melancholic despair (Krauss & Starkman, 2000), we need to be ready to fight the ultimate battle between Good and Evil: Life vs. Dark Energy (Hooper, 2018). Space.…”

“…(i) If our intelligence is still at the same level as today, we will follow Hooper (2018) and start pushing all our stars to keep the Galaxy together and our energy source accessible. In order to make sure that we need all the energy we harvest, we will build our spaceships in form of giant SUVs which are constructed such that they have a decent wind-resistance even in the interstellar medium, and we will cause a greenhouse effect in the Galaxy so strong that Dyson-trees (Dyson, 1997) start to grow on molecular clouds.…”

Habitable Zones around Almost Extremely Spinning Black Holes (Black Sun Revisited)

“…The existence of a temperature gradient between a low-entropy radiation source that heats the (exo)planet and a cold part of the sky that allows the discharge of waste heat is a necessary condition for the existence of life processes. We can also consider alternative scenarios of extraterrestrial life (see, e.g., Sandberg et al (2017); Hooper (2018)), but this will not affect the essence of our thermodynamic considerations. Such a situation corresponds very well to the case of an (exo)planet heated by a standard parent star.…”