I went to this year’s second Everhart Lecture yesterday by Josh Spurgeon, who is working with Harry Atwater and Nate Lewis, trying to develop cheap, scalable solar cells. As with most of the Everhart Lectures, it was a very well presented talk. Unlike many of them, it was directly relevant to a real-world problem: how can humanity continue to utilize on the order of 10TW of power, without changing the composition of the atmosphere (see Nate Lewis’ excellent presentation for more information). The ultimate solution to that problem will almost certainly involve directly capturing incident solar energy, because the potential resource available is both vast and relatively concentrated, when compared to other sources of renewable energy. But solar has two very serious problems today: it is expensive (both in absolute terms on a per watt installed basis, and in an up-front capital expenditure sense), and it is not available when the sun isn’t shining. Whatever the solution looks like, in order to scale up to 10TW, it needs to use only earth-abundant, non-toxic materials. In semiconductor photovoltaics then, silicon probably has an unassailable lead. It’s the second most abundant element in the Earth’s crust, and it’s about as toxic as sand (though silicon semiconductor fabrication has serious toxicity associated with it and certainly needs to be made closed-loop). Exotic materials like cadmium-telluride, and copper-indium-gallium-selenide (CIGS) are unlikely to scale to tens of terawatts, simply because of the limited availability of elements like indium and tellurium. Additionally, owing to the vast silicon microprocessor industry, we are much better at micro and nano-scale manipulation of silicon than any other material on Earth (ignoring for the moment biological systems).
Tag: public
Dijkstra, the Buxton Index, and the Prisoner’s Dilemma
EW Dijkstra, the computer scientist, was fond of using a metric called the “Buxton Index“, which conveys the timescale on which an individual or institution makes its plans. He thought that a lot of failures to cooperate, and other kinds of conflicts, were ultimately due to different actors having different time horizons. Here are three of his short essays mentioning it:
- On the fact that the Atlantic Ocean has two sides
- On the phenomenon of scientific disciplines
- The strength of the academic enterprise
It’s interesting in the context of, e.g. the Prisoner’s Dilemma, in which only an indefinite (or infinite) timescale can reliably result in cooperation (as detailed in Robert Axelrod’s book, The Evolution of Cooperation). It certainly seems like we should have some metric of this kind in mind when considering the behaviors of various institutions.
Dijkstra notes that interestingly (at least in the west) virtually all of the institutions which are more than 500 years old are universities (two churches and two governments also qualify, out of 66 total).
I think its funny that Dijkstra was essentially blogging, by fountain pen, for decades. He wrote out hundreds of these short numbered essays longhand, and sent copies of them to friends, who then copied them, and sent them on, etc. He kept doing it this way even after everyone had e-mail! I had no idea he was such an interesting guy.
The Time Value of Information and Material Wealth
Conventional economics says money today is worth more than money in the future. This is why people are willing to agree to pay interest on a loan (and why a creditor requires it). How much more money is worth today than in the future is determined by the discount or interest rate (depending on what kind of calculation you’re doing). This would hold true, say the economists, even if we lived in a hard money world (e.g. silver and gold), and even after accounting for the risk of default by the debtor, because of opportunity costs. Creditors and investors presumably have a choice as to what they do with their money. Sitting on your pile of treasure in a vault ensures that it doesn’t get smaller, but it also doesn’t get bigger. When they choose to make a loan or invest in an enterprise, they are, it is assumed, seeking the best possible (risk adjusted) return, and so the value of a given present pile of money at some time in the future is the principal invested plus the return earned between now and then. If you can make 10% per year on some investment, and you have $100, and someone offers to give you $105 a year from now in exchange for your $100 now, all else being equal, you refuse, invest at 10%, and end up with $110 next year instead.
This conception of money is somewhat problematic, as it tends to render everything in the time and world of your grandchildren essentially worthless in the present. Even at a modest 5% discount rate, $100 a century from now is only worth $0.59 today. I think the problem comes largely from the convolution of informational and material wealth, and our habit of representing both of them with the same currency.
Continue reading The Time Value of Information and Material Wealth
Have you seen the light?
As animals, and especially visual animals at that, we have a particular experience of the light. For us it is illumination, information about our surroundings. For that purpose moonlight or even starlight will do. And for tens of millions of years, that’s all we ever saw. Somehow a few of us made it through the Permian extinction, and into the Triassic, but the ascendancy of the dinosaurs eventually forced us into the darkness of the night. Our world became dim, and our eyes went colorblind. Most mammals today see only two colors, but a few of us have re-evolved a third photoreceptor. Three colors is still inferior to the four or five or six seen by many near-surface fish, birds, reptiles, insects, and other arthropods. The stomatopods are almost biological spectroscopic imaging systems, with 12 color channels in each of their independently movable trinocular eyes. We are lesser than the eyes that never left the light. They stole the colors from us and made us hide within the night. They kept the sun for themselves, not knowing that our small and furtive ways, our burning endothermy and our fur would see us through the aftermath of the KT impact.
Dittoheads and Socialists
I have to say, it’s been a long time since I felt like the Democrats did anything politically savvy, but I think running with the recent re-branding of Rush Limbaugh as the head of the GOP qualifies. Incredibly both Fox and the Huffington Post seem almost to agree on the substance of the story: the GOP is currently in disarray, and searching for leadership. The dittohead masses that follow Limbaugh are a big enough voting bloc that the party’s current nominal spokesmen cannot be seen to oppose him too much outright, lest he savage them from his bully pulpit.
Not All Capital is Fungible
There are only two real pools of capital: alternatively natural or human, external or internal, material or informational.
Natural (external, material) capital is the pre-existing wealth of the world, which was not dependent on our organization or existence: the metals we mine, the trees, the fresh water, the fisheries, solar energy, the fossil fuels, the potential for agricultural produce (as a co-location of soil, water, and climate). Human (internal, informational) capital is the value inherent in technology, skill, organization, understanding, and knowledge.
I Was the Victim of a Series of Accidents
Kurt Klein “wonders how liberals rationalize a Secretary of the Treasury who cheated on his taxes ($34,000–oops! rounding error)”. Well, here’s how I would do it. Not that I’d necessarily want to be called a liberal:
Francis Collins has no evidence for God
I can’t say that I’m surprised, but what Francis Collins presented in his talk last night at Caltech as constituting evidence for God’s existence was utterly unconvincing. However, what he said and the questions which followed were vastly better framed, less offensive, and in some important respects much closer to the truth than the talk that Richard Dawkins gave at Caltech in 2006 when he was touring for his book The God Delusion (which was ultimately so unpleasant and ill conceived that even I, an atheist who basically agrees with Dawkins’ criticisms of religion, am unable to recommend it). You can watch or listen to an earlier version of Collins’ talk on the Veritas Forum website. It’s in support of his own book, The Language of God: A Scientist Presents Evidence for Belief.
Francis Collins at Caltech and the future of genomic medicine
Went to Francis Collins’ afternoon talk “fireside chat” with David Baltimore on the future of medicine, as illuminated by genomic work. Too much introduction and rambling biographical information, but some good discussion anyway. I thought his best comments had to do with the positive effects of the open data model that the Human Genome project initiated – it’s had a long lasting impact on the entire field of genomics, and thank goodness! Also, he mentioned that as of now, there aren’t any major studies seeking to correlate and analyze the relationships between genotypes, phenotypes, and environment in the human population, and that such a study is really what’s needed to truly understand what’s actually heritable, what our real low frequency (rare allele) genetic variation is like, and what kinds of effects environmental factors play. He pointed out, interestingly, that we don’t need to wait until thousand dollar genomes are available to start this study – what we need to do is get people signed up, and start tracking their health history and environmental factors, and we can sequence them when it becomes cheap enough. He suggested that we ought to do this for roughly 500,000 people, and that it would likely cost on the order of half a billion dollars a year, and need to run for a few decades. And then we’d know, and medicine would be forever changed. He also suggested that those $1000 genomes are likely on the order of 5 years away. Really, once we’ve got fast, cheap sequencing – this study will almost do itself, so long as we can at some point get access to the medical histories and genomes of people. The real value add is in starting it now, so we have the information as soon as possible, and in getting all the environmental/lifestyle data, in addition to the healthcare records.
Continue reading Francis Collins at Caltech and the future of genomic medicine
The Edge’s Annual Question for 2009
From the Edge, and their annual “World Question Center” for 2009.
What will change everything? What game changing scientific ideas and developments do you expect to live to see?
Many thoughtful answers, including a particularly good one about climate, likening potential abrupt state changes to unpredictably soundly sleeping giants that we do not want to awaken:
Unfortunately, we are discovering more giants that are probably lighter sleepers than the thermohaline circulation (THC). Seven others — all of them potential game-changers — are now under scrutiny: (1) the disappearance of summer sea-ice over the Arctic Ocean, (2) increased melting and glacier flow of the Greenland ice sheet, (3) “unsticking” of the frozen West Antarctic Ice Sheet from its bed, (4) rapid die-back of Amazon forests, (5) disruption of the Indian Monsoon, (6) release of methane, an even more potent greenhouse gas than carbon dioxide, from thawing frozen soils, and (7) a shift to a permanent El Niño-like state. Like the THC, should any of these occur there would be profound ramifications — like our food production, the extinction and expansion of species, and the inundation of coastal cities.
We’re wallowing in the fat tails.