Civilizations at the End of Time: Black Hole Farming

My go-to entry point for exploring those kinds of questions was Isaac Arthur. He goes into the Kardashev scale [1], dying Earth [2], dying stars [3], farming black holes [4], and going past iron stars [5]. A Boltzmann Brain's description bears remarkable similarity to the Judeo-Christian concept of God before time begins, and has been fertile ground for ruminations [6], though none with any verifiable claims backing them in our current knowledge of physics [7]. Now if we could only restructure our implementation of capitalism to be pinned to advancements towards resolving physics questions to survive those kinds of timescales and challenges instead of locked down to a single planet's worth of baryonic matter and cognitive capacity... [1] [link] [2] [link] [3] [link] [4] [this video] [5] [link] [6] [link] [7] [link]

> Consciousness is an emergent property of computation It's interesting to see the negative comments about this here because I agree with you. "Consciousness" or even "sentience" is notoriously difficult to define. Even defining what an organism is isn't entirely obvious (eg some might consider a colony of ants or bees as being organism-like). Our views tend to be extremely human-centric because we can relate. I imagine once we actually invent an AGI many will debate if it's truly sentient or conscious for a long, long time afterwards. > Computation is more efficient in smaller, less massy media There are physical limits on computation. A smaller package ultimately has a lower limit. That alone will (IMHO) keep a space for very large computational units. At the top end of this is Matrioshka Brains [1]. A digital existence looks highly likely in the black hole era of the universe [2]. This is the era after all the stars have faded out and will be much longer (based on current understanding) than the stellar era, so much so that the 13-14B year lifetime of the universe thus far will be like the blink of an eye. As for detecting communication, that's too narrow a focus. Whether we're miniscule cyborgs that communicate with qubits or living as virtual beings in a world-sized computer, the ultimate limits of what any such civilization can do is is the amount of energy they can consume. More energy means more is possible. So even if we end up living as a K2 civilization in a billio

A lot of thought has gone into far-future uses of black holes: - Black hole starships [1] - Weaponizing black holes [2] - Colonizing black holes [3][4] - Black hole computers [5] Black holes may be the most efficient forms of batteries and power generators yet conceived. If our model of the Universe is mostly correct then the Univese will have an era of stars that will ultimately burn through all the fuel and we'll just be left in the dark with black holes that will evaporate over an extraordinarily long period of time, many orders of magnitude than the stellar era. For propulsion, this ultimately comes down to photons have momentum. We can use them to move things. This is the idea behind the solar sail. Black hole propulsion revolves around how you use the momentum from an evaporating black hole into motion for a ship. There are a bunch of factors to balance out here. Too small and the black holes dies too quick (and is too energetic). Too large and it's too hard to move and has a lower output and so on. Turns out there's a sweet spot for all this of about a million tons, which is in the realm of what we call Kugelblitz black holes. I personally think using stellar output to accelerate and decelerate ships it he most likely outcome for a spacefaring species. If fusion ever becomes viable this may be an alternative for when you're not near a star. Ultimately black holes may replace that but there are significant theoretical and engineering challenges to that like how you'd ev