Writing truly hard science fiction, such as Will of the Stars means contending with the laws of physics as they actually are, rather than as we would like them to be.

In particular, I am going to assume that the speed of light is a real constraint and that the various tropes about FTL (wormholes, warp drives, and so on) are not feasible. Given this assumption, some futurists have modeled the speed of interstellar expansion as approaching the speed of light. The idea is that sufficiently advanced technology, intelligence, and engineering could eventually allow humanity, or another species, to colonize worlds almost as quickly as light can travel between them.

However, if we look at the laws of physics as well as the economic and physical incentives that govern expansion across the stars, there are many constraints on interstellar travel that appear long before we reach the speed of light.

Why is this important? Correctly estimating the speed at which a high-tech civilization can spread across the stars changes our perspective on the Fermi paradox. If we don’t see other civilizations because they are confined to individual star systems, or because they expand at only a small fraction of [...]

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First published:
September 6th, 2026

Source:
https://www.lesswrong.com/posts/cKSJk2GKk3ptAJKKp/heat-dissipation-is-the-main-constraint-in-interstellar

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Narrated by TYPE III AUDIO.

“Heat Dissipation Is the Main Constraint in Interstellar Travel” by Pasha Kamyshev

LessWrong (30+ Karma)

“Heat Dissipation Is the Main Constraint in Interstellar Travel” by Pasha Kamyshev