Sunday, May 31, 2020

Experience curves, large populations, and the long run

If our civilization avoids catastrophe, will we generally be able to advance technology to close to physical limits, match or exceed observed biological abilities, and colonize the universe? Or will we be stuck in a permanent technological plateau before that, reaching a state where resources are insufficient to make the breakthroughs to acquire resources and continue progress? Experience curves, which forecast cost improvements in technology as a function of cumulative production, are a popular tool for technological forecasting and perform relatively well compared to other statistical approaches, although they inevitably have significant and increasing error as one extrapolates further. If we consider the maximum energy resources and population of the Earth, combined with the potential lifetime of human civilization (absent existential catastrophe), experience curves extrapolate to immense technological improvements (constrained by physical limits), more than sufficient to colonize the rest of the solar system, which in turn yields a billionfold increase in potential scale to fund interstellar colonization. Such extrapolation would suggest matching or exceeding biological capacities we currently lack, such as the computational efficiency of brain tissue, or the rapid energy payback of algae as solar energy and manufacturing devices.

Thursday, May 28, 2020

Terrestrial solar energy could eventually support extremely large economies and populations

If we are interested in whether Earth's civilization could ever reach various technological milestones, or long run economic output and populations that Earth could sustain, the terrestrial solar energy resource can provide helpful information. Using efficiencies of the best lab solar cells, covering the earth with solar panel platforms could provide a thousand times as much energy as our civilization currently uses, and more than a hundred times the production of the terrestrial biosphere. Historical experience curve and cost data suggest this energy supply could be much cheaper than current energy prices, although with increasing overhead costs as less desirable areas such as ocean platforms and less sunny lands are used. Energy payback times are already under a year for energy-efficient solar in good locations, and have been falling along with prices, so solar energy can power its own construction, and with advanced robotics and AI might eventually grow at extremely rapid rates. 

Saturday, May 23, 2020

The High Frontier, space based solar power, and space manufacturing

The High Frontier, published in 1976 by Gerard K O'Neill, lays out a vision of economically profitable space colonization in artificial orbital habitats, and guessed (while disclaiming it as prediction) that it was "unlikely" that a space community would not be established in 30 years. I was interested in why those forecasts were made, and why they turned out wrong, as data points for thinking about forecasting future technological developments. The book lays out a case that in the long run space habitats can support immensely larger populations and wealth than the planets in the Solar System. In the medium term it argued that a government program to invest hundreds of billions of dollars to build space factories and Lunar mining facilities would eventually let them produce solar power a few times more efficiently than terrestrial solar power production, and that this would drive space colonization. This seems to have been doomed for multiple reasons, radically underestimating launch costs and likely fatally underestimating the increased costs of space production (to be paid for out of a 2-3x improvement in solar radiation), as well as requiring immense government funding. As a means to improve solar power cost-effectiveness, it would have been far inferior to solar cell R&D. Subsequent orders-of-magnitude improvement in launch costs per kW of solar cells make space-based solar more plausible than at the time, but the challenge of competing with terrestrial solar and especially terrestrial scale economies of industry remains high.

Saturday, November 30, 2019

Person-affecting views may be dominated by possibilities of large future populations of necessary people

On symmetric person-affecting views (PAV), in choosing between actions only necessary people, those who will exist regardless of our immediate choice, count while those whose existence is contingent on our choices are ignored. Chaotic 'butterfly effects' mean that almost any terrestrial action will shortly scramble the genetic makeup and identities of future terrestrial births. Thus philosopher Michael Plant invokes symmetric PAV to say that '[o]n this, roughly speaking, the well-being of future entities, human or non-human, does not count" and to argue in favor of a focus on short-run impacts on long-lived existing creatures (humans and dogs, but not chickens or ants) rather than long-run consequences of altruistic interventions, since vast future populations would be composed of contingent rather than necessary people. However, the empirical underpinnings of this move are questionable: there are reasonable possibilities on which astronomically large populations of necessary people will exist, and credence in such possibilities will mean that they account for the bulk of expected impact on necessary people. I raise three such possibilities: technological life extension, contact with distant aliens, and fission cases.

Saturday, October 20, 2018

Financial returns of interstellar colonization for the sedentary

Summary: In thinking about the likelihood of interstellar colonization by our civilization, or possible alien civilizations, one question is motivation: how strong are the incentives to do so? If moderately fast self-replicating probes can build infrastructure in a new solar system and send back information or material goods requiring extensive experimentation or computation to produce, then even at current market interest rates a colonization mission could deliver extremely high return on investment. For patient long-lived decision-makers with strong property rights or stability, returns could be overwhelming.

Friday, October 19, 2018

Flow-through effects of innovation through the ages

Summary: Per the previous post, it appears that growth impacts of saving lives have historically dwarfed the immediate effects, by increasing technological innovation that eventually led to the rich and populous modern world. Active work on technological innovation contributes more to technology than the average of all activity in society, and so might be expected to have larger growth effects. Moreover, in ancient times not only did society have smaller population and output, it also invested much less of those resources into R&D. The greater neglectedness raised the marginal impact of ancient R&D enormously, so that past altruists who contributed to innovation could have had multiple orders of magnitude more impact on long-run living standards and years of life lived than those who saved lives or provided direct aid. The strength of this preference increases enormously as we consider earlier periods in history.

Wednesday, October 17, 2018

Flow-through effects of saving a life through the ages on life-years lived

Summary: Historically, human populations were much smaller, and humans have long contributed to a process of technological accumulation that lead to current enormous human populations. Thus, saving a drowning child 10,000 years ago would have, by increasing economic output and technological advance, lead to hundreds of additional human lives by today, and potentially far more in the future. Because past populations were smaller by a greater factor than they were poorer, the ancients' opportunities to bring about QALYs may be much greater and closer to those of moderns than is sometimes thought, at least within the field of local direct life-saving. Impacts were also enormously greater in comparatively non-Malthusian periods, when a saved life could compound at high local population growth rates. In some ways, this is a historical analog to Nick Bostrom's 'Astronomical Waste' argument, showing that the basic logic of longtermism has held in the past in at least some domains. However, expediting growth is a relatively easy change to transmit over long periods, whereas trajectory changes that attempt to shape the character or actions of society at future technology levels (rather than when they are reached) face the problem of decaying influence.