# The Scale of Our Future: Nick Bostrom on the Cosmic Endowment > Coverage of lessw-blog **Published:** March 28, 2026 **Author:** PSEEDR Editorial **Category:** risk **Tags:** Existential Risk, AI Alignment, Cosmology, Longtermism, Nick Bostrom, Megastructures **Canonical URL:** https://pseedr.com/risk/the-scale-of-our-future-nick-bostrom-on-the-cosmic-endowment --- lessw-blog highlights Nick Bostrom's quantitative analysis of the cosmic endowment, exploring the staggering upper limits of future human-like lives and framing the ultimate stakes of existential risk and AI alignment. In a recent post, **lessw-blog** discusses Nick Bostrom's detailed exploration of the "cosmic endowment." The analysis attempts to quantify the absolute limits of what an Earth-originating intelligent civilization could achieve in terms of resource acquisition, cosmic expansion, and the creation of future lives. Bostrom, a prominent figure in existential risk and artificial intelligence safety, provides a mathematical framework to conceptualize the sheer scale of our potential future. This topic is critical because understanding the theoretical limits of our future directly informs how we prioritize existential risks today. In the fields of AI safety and longtermism, the "cosmic endowment" represents the total potential value-or disvalue-that could be realized if humanity survives and reaches technological maturity. By calculating these bounds, researchers can better frame the ultimate stakes of artificial superintelligence alignment. If the potential future is astronomically large, the imperative to avoid premature extinction or unaligned AI becomes correspondingly massive. The discussion connects theoretical cosmology and practical risk management, illustrating exactly what humanity stands to lose if we fail to navigate the transition to advanced machine intelligence safely. lessw-blog's post outlines Bostrom's calculations, which factor in strict cosmological constraints, primarily the positive cosmological constant and the impossibility of faster-than-light travel. Bostrom argues that a technologically mature civilization could deploy von Neumann probes-highly advanced, self-replicating spacecraft-traveling at anywhere from 50% to 99% of the speed of light. Remarkably, achieving these speeds is energetically attainable using only a small fraction of the resources available within our own solar system. Once launched, these probes could theoretically reach between 10^10 and 10^12 stars before the accelerating expansion of the universe permanently pushes the remaining galaxies out of reach. The post further breaks down the carrying capacity of this accessible universe. While initial, conservative estimates suggest such an expansion could support 10^16 human lives-assuming 10% of stars have habitable planets supporting a billion individuals for a billion years-Bostrom posits this is a severe underestimate. By moving beyond planetary chauvinism and engineering O'Neill cylinders, disassembling non-habitable planets for raw materials, and harvesting interstellar matter, an advanced civilization could maximize its energy and spatial efficiency. Under these optimized conditions, the potential carrying capacity could increase to an estimated 10^34 human lives. This quantitative baseline is essential reading for anyone interested in longtermism, astrophysics, or the philosophical implications of advanced technology. It forces readers to confront the astronomical scale of what is at stake in contemporary technological development. To explore the full mathematical models, the mechanics of von Neumann probes, and the cosmological breakdown, [read the full post on lessw-blog](https://www.lesswrong.com/posts/GLD5AiiQJqFbKX9vo/nick-bostrom-how-big-is-the-cosmic-endowment). ### Key Takeaways * Technologically mature civilizations could use self-replicating von Neumann probes traveling at up to 99% of the speed of light to colonize the accessible universe. * Cosmic expansion and the speed of light impose a hard upper limit, restricting access to approximately 10^10 to 10^12 stars. * Conservative estimates place the potential future population at 10^16 human lives, but advanced megastructures like O'Neill cylinders could increase this to 10^34. * Quantifying the cosmic endowment is crucial for framing the stakes of existential risk and AI alignment, highlighting the astronomical value of humanity's long-term survival. [Read the original post at lessw-blog](https://www.lesswrong.com/posts/GLD5AiiQJqFbKX9vo/nick-bostrom-how-big-is-the-cosmic-endowment) --- ## Sources - https://www.lesswrong.com/posts/GLD5AiiQJqFbKX9vo/nick-bostrom-how-big-is-the-cosmic-endowment