Sunday, October 29, 2006

Vernor Vinge: Rainbows End

Vernor Vinge's Rainbows End is a near future story, centered around the same San Diego high school as his Hugo-winning 2002 novella Fast Times at Fairmont High. This is a fun story to read, but not up to the standards of his galaxy-spanning stories. As a matter of fact, I thought Fast Times was more effective, though it's a trope that it's easier to write a punchy short story than an effective full-length novel.

In Rainbows End, we watch Robert Gu recover from alzheimer's after getting a newly introduced therapy. As Gu regains his mental faculties, he realizes that he's lost some of his strengths, and that he'll have to develop new abilities in order to cope with the world as it has become. The bout of alzheimer's provides a nice plot device to allow Gu to skip forward in time, missing a period of technological development and having to catch up. In Vinge's future, society has caught on to the fact of Future Shock, and provides special classes to give people who have slept through the accelerating change a chance to catch up. It's not quite a singularity, but there are certainly many people who were left behind and have realized that coping with daily life requires more familiarity with modern technology (consensual reality, ubiquitous private instant messaging, sophisticated wearables, tools and transportation that can only be controlled from personal remotes that everyone is assumed to carry.)

The large-scale conflict that drives the story concerns electronic security, and a biotech development that threatens people around the world. The plotters are a global cabal, with their fingers in every pie and the ability to subvert many of the underlying technologies. Gu's circle includes counter-terrorism specialists as well as loving family members who use the ubiquitous surveillance technology activities to follow his activities when there are hints that he's involved in events beyond his recovering abilities.

Libertarians will find much to ponder in the ubiquitous surveillance, the government's fundamental control of the foundations of technologies, and the shape of this not-too-unlikely future. But most of this is simply background for the story here, and Vinge doesn't bother to say or even imply much about the implications for freedom or personal responsibility. Some of the plotters seem to be able to pursue the plots because of the power they get from their role in government, but they are stopped by people who wield government power wisely and benignly.

This is a good book, but not a great one. I don't think it will be a strong contender for the Prometheus Award this year.

Thursday, October 26, 2006

Edward O. Wilson: On Human Nature

Edward O. Wilson's On Human Nature is an enjoyable read. (It won a Pulitzer Prize, so this is no surprise.) Even though it was written in 1978, it continues to provide a good overview of much that is still held to be true about human biology and sociology. There are chapters addressing Heridity, Agression, Sex, Altruism, and Religion. Wilson is a gifted writer, and can explain subtle concepts with clarity. The opening chapter posits that we are evolved creatures, and that our brains are effectively machines constructed out of billions of nerve cells that bottom out in chemical and electrical interactions. With this as context, Wilson says that the central dilemmas of our existence are that we have no pre-established goals, and that our development of morality on a scientific basis has been short-circuited by the fact that much of our ethical instincts are inculcated by our heridity and environment. In order to understand how we can have goals beyond those evolution set for us, or understand morality in any depth, we first have to understand the biases that evolution has built into us.

The heart of the book is an exploration of what human nature consists of. Wilson provides clear contrasts with the many other creatures (from insects to higher mammals) that he has studied. He points out the myriad ways that social behavior differs across species, both to show how different thinking creatures might be, and to provide context for an argument that the "natural" drives we have evolved shouldn't be treated as guides to correct behavior. If religion can be systematically analyzed and explained as a product of the brain's evolution, its power as an external source of morality will be gone forever. He follows that with this statement of principals:

The core of scientific materialism is the evolutionary epic. Let me repeat its minimum claims: that the laws of the physical sciences are consistent with those of the biological and social sciences and can be linked in chains of causal explanation; that life and mind have a physical basis; that the world as we know it has evolved from earlier worlds obedient to the same laws; and that the visible universe today is everywhere subject to these materialist explanations.

The one thing I would fault Wilson for is for not addressing his first dilemma more strongly. I think he did a good job of showing that religion and our instincts are not a sufficient basis for establishing goals for us to pursue. But that doesn't leave us adrift in an uncaring cosmos; the first task of any maturing person is to discover or invent their own goals. Morality and ethics provide boundaries on that search, but everyone has to find their own destination. Wilson instead falls back on a shared goal of progress and scientific exploration. I do admire his eloquence. This is how he closes the book:

The true Promethean spirit of science means to liberate man by giving him knowledge and some measure of dominion over the physical environment. But at another level, and in a new age, it also constructs the mythology of scientific materialism, guided by the corrective devices of the scientific method, addressed with precise and deliberately affective appeal to the depest needs of human nature, and kept strong by the blind hopes that the journey on which we are now embarked will be farther and better than the one just completed.

Wednesday, October 25, 2006

Epigenetics and Methylation

Science News (June 24, subscriber-only) had a nice feature article on Epigenetics and methylation's role. I thought their explanation of how the epigenetic marks attach to DNA was particularly clear. I've read about methylation before, but never come across a description of the mechanism.

As early as the 1940s, researchers who couldn't explain some of an organism's attributes by straightforward Mendelian genetics started calling these aberrant traits epigenetic, says Randy Jirty, a researcher who studies gene control at Duke University in Durham, N.C. "'Epigenetics' literally means 'above the genome,'" he explains.

Scientists eventually learned how apt the name was. Inspecting the double helix turned up hundreds of thousands of what scientists colloquially call "marks"—places where DNA is tagged with carbon and hydrogen bundles known as methyl groups. Enzymes attach methyl groups only at points on the genome where two DNA components—cytosine and guanine—meet. These components often cluster near the beginning of a gene, where proteins attach to turn on genes. If a methyl group blocks a protein from binding, the gene typically stays switched off.

In recent years, scientists have learned that methylation isn't the only mark that changes whether genes are expressed. Various chemical groups clip on to histones, the spools around which DNA wraps when it condenses into chromosomes. These groups can affect how tightly DNA is packed. Although histone modification is not as well studied as methylation, researchers have shown that genes on loosely packed DNA are more likely to be expressed than are those on DNA that's tightly wound.

Most of these epigenetic marks are set by cells long before an animal's birth, says Jirtle. Each type of cell, from liver to skin to muscle, carries a distinct pattern of methylation and histone modification that, for the long term, switch genes on or off in the pattern necessary for the cell to do its job.

However, Jirtle adds, not all of these marks are set in stone. Outside factors during development can change which DNA segments are epigenetically modified, setting the stage for traits that linger into adulthood.

Jirtle's group did some studies with mice whose coat color can be changed epigenetically according to whether their diet is enriched or impoverished with methylation-inducing supplements. The supplements also affect disease susceptibility. They can prove that methylation mediates the signals because they can trace the presence of the methyl groups in subjects that receive different treatments, and they can change the signals by administering drugs that add or remove methyl groups selectively.

The interesting consequence of epigenetics via methylation is that parents and uterine environment have some control of the epigenetic markers of offspring separate from the DNA's message. Recent work is showing that the epigenetic markers can also be changed throughout an organism's lifespan, changing susceptibility to diseases and predisposing other somatic effects. None of this is surprising; I'm describing it merely to provide background for anyone who wouldn't otherwise understand the context. The benefit here is the clear explanation of how the methyl decoration works. Wikipedia has a more in-depth explanation and provides more discussion of consequences. I still like Science News' simple clarity.

Sunday, October 22, 2006

Space Elevator Challenge Results

The Second Annual X Prize Cup was held in Las Cruces New Mexico this weekend. 4 events related to space development were scheduled: the Space Elevator challenge in two parts (a climber competition and a tether competition); a lander challenge to develop a rocket-propelled autonomous vehicle that can take off, hover, then land again; and an exhibition for the Rocket Racing League. The engine for the Racing Rocket wasn't ready, so the craft was unveiled but not flown. I didn't find any reports on the Lunar Lander challenge; I assume no one won the competition. All the preliminary reports described mishaps of various sorts.

The most exciting competition was the climbing challenge. Competitors had to build a climber that could scale a specified ribbon at a speed of at least 10 meters per second and then descend. Power had to be beamed to the climbers from the ground. Winds were much higher than expected in Las Cruces, and as a result, the competition tether swung back and forth, moving many climbers in and out of their power beams. Two of the teams that tried to qualify used microwaves to beam power to their climbers; the Airport announced on the day of competition that they wouldn't allow microwave-based systems. A Spanish team shipped its climber by UPS, but it was lost en route. Three other teams were scheduled to compete, but various mechanical problems and mishaps got in their way. That leaves 6 teams that managed to qualify:

Climber Qualifiers

  • USST (University of Saskatchewan Space Design Team) climbed in 58 seconds. They didn't manage to descend in the alloted time, and there was some question as to the actual height of the climb. If it was 50 meters, they didn't reach the speed required to win the challenge purse of $200K, while if it was 60 meters, they would have been fast enough.
  • LiteWon from Westmont High School in Campbell, California first climbed the tether in 5:31, and in a repeat attempt managed to improve that to 2:02. Their (controlled!) descent was very fast at about 10 seconds.
  • TurboCrawler from Germany had problems with their controller in the final climb, then managed the climb in 3:27. They used two spotlights totaling 30 kilowatts to power their climber.
  • Climber 1 from the University of Michigan ascended in 6:40; they were fast enough when the climber was illuminated, but the wind kept moving the climber out of the beam.
  • Kansas City Space Pirates climbed more than half way, but couldn't complete the climb due to the winds.
  • Snowstar from the University of British Columbia couldn't get a grip on the tether during the competition.

tether qualifiers

Four teams entered the tether competition. They were required to submit a 2 meter tether that couldn't weigh more than two grams. They would then compete in pairs to see which could hold a heavier weight. The four qualifiers were Astroaraneae, UBC, Centaurus Aerospace and Bryan Laubscher. All the competitors met the weight limit, but only Astroaraneae met the 2 meter minimum length, so the others were all disqualified.

In a series of friendly competitions, UBC outlasted Bryan's submission at 531 pounds; UBC broke at 880 pounds while Centaurus Aerospace survived that weight. Astroaraneae held until 1335.9 pounds against the house entry. The house tether was allowed to weigh three grams and was the target to beat in order to win the $200k in prize money. The organizers then attempted to break the house tether (in order to provide a benchmark for next year's competition), but the pulling machine jammed.

The space elevator blog had play-by-play on the competitions. The Space Elevator Reference also had coverage that's worth looking at. has quite a few videos (mostly promos). YouTube has videos of some of the qualifying runs. I didn't find any of the actual competition runs. They also have other videos related to the x-prize events. personalspaceflight has more blogging, focusing on the rocketry side.

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Saturday, October 21, 2006

Charles Stross: The Clan Corporate

Charles Stross's The Clan Corporate is the first part of a new story in the Merchant Princes series. (See my review of The Family Trade and The Hidden Family.) This segment is reasonably well told, but very inconclusive. Clan opens up some new issues, but doesn't resolve anything. In this installment, Miriam Beckstein finds herself unable to get much done because all the powerful people around her distrust her motivations. She manages to escape their clutches at one point, but digs herself a deeper hole, and ends up even more constrained in her actions. In many ways the subplot dealing with Mike Fleming, and his work helping to unravel the mystery from the government's point of view, was the most interesting part of the book. The government sets up a cross-agency task force, and manages to learn a bit about the abilities of the family members, and even make some initial incursions into their territory. There are connections to the modern anti-terrorist complex, but they aren't explored in any depth.

I didn't notice anything here that would make the book relevant to the Prometheus awards. The writing is good, but since it's obviously the first part of a longer work, and leaves everything up in the air, it's unlikely to attract attention for the writing. And there's no hint of libertarianism; even the explorations of the development of commerce, and the comparisons of the economic effects of different approaches that I liked so much in Hidden Family are missing since Miriam spends nearly all her time stuck in world 2. I recommend continuing to follow the series, but this book isn't much more than a bridge to the next part.

Joseph Mazur: Euclid in the Rainforest

I received a copy of Joseph Mazur's Euclid in the Rainforest as a going away gift when I left CommerceNet. Will figured out that I like reading books of puzzles, logic, and math.

It's a rambling approach to a lot of interesting byways in math and logic. The style switches between travelogue and reminiscence, always with in-depth side journeys into history of math and various logic puzzles.

The first section is presented as the story of the narrator's trip through the Amazon basin, running into various characters with interesting problems that require logical reasoning and an awareness of math or geometry to solve. How powerful a winch do you need to pull a two-ton truck up a 45 ° slope? In explaining the answer, we see the first of many proofs of the Pythagorean Theorum. At this point, the narrator also starts showing us how to disentangle syllogisms. His example asks what you can conclude from the following statements?

  1. Atoms that are not radioactive are always unexcitable.
  2. Heavy atoms have strong bonds.
  3. Uranium is tasteless.
  4. No radioactive atom is easy to swallow.
  5. No atom that is not strong is tasteless.
  6. All atoms are excitable except uranium.
He goes on to talk about Infinity and Probability in engaging ways. All in all, an enjoyable book. Not very deep; not much that was new, but the material was presented in a way that kept up my interest.

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Saturday, October 07, 2006

James Surowiecki: The Wisdom of Crowds

I saw James Surowiecki give a talk at a prediction market conference before I read his book, The Wisdom of Crowds . The talk was interesting and he demonstrated a strong grasp of the market and an appreciation for its value. He engaged the audience in a discussion on how Prediction Markets could be made to work better. I was quite impressed, but I assumed it was mostly unrelated to the book. I was wrong.

Surowiecki has done a commendable job of presenting broad coverage of the many ways in which crowds can work together to produce results that exceed those of individuals or poorly coordinated groups. He also explains the strengths and limitations of the effect--when groups can be expected to outperform individuals, and when will they underperform.

The book starts with some simple examples: taking the average of many people's uninformed guesses can work very well when everyone has a reasonable idea of the plausible range of values under consideration. Crowds do quite well at guessing the weight of a person or the number of jelly beans in a bowl. They don't do as well at guessing the distance to the moon.

Surowiecki explores different institutions we use to make decisions and predictions looking for rules of thumb about what makes each work well and what problems each is suited for. His subjects range from markets and corporations to democracy, traffic and science.

It's hard to find this summed up in one place in the book, but Surowiecki's thesis is that there are institutions that can do a good job of getting good decisions and predictions from people even when none of the participants could do as well, and that the important factors are that the institution is appropriate for the task, and the crowd is diverse and independent. When institutions encourage or allow people to follow one another, the crowd's independence is undermined, and the outcome can be swayed by strong individuals. If the participants all come from the same background, or share a point of view (because of the way they were selected, or because the institutional setting channeled their views) then you don't get robust results.

Surowiecki comes across as a strong proponent of markets in the book, but he also describes situations that are more suited for other tools. He lauds open source software development, and also points out that decentralized coordination without prices can work well for managing traffic or leading scientists to expand the frontiers or our knowledge. An enjoyable read with much to recommend it.

Sunday, October 01, 2006

Appreciation-indexed Mortgages

A recent article in the Economist talked about new loan products that are currently available only overseas (Britain and Switzerland) that embody one of the ideas that Robert Shiller talked about in The New Financial Order. Shiller pointed out that the financial industry has learned, over the last few decades, how to package up risks in many new ways to allow companies and people who are subject to those risks to sell them to other parties in a way that can be beneficial to both. Insurance (health, employment, hazard, auto) were the first examples; recent innovations like currency swaps help companies with too much exposure to currency fluctuations trade it away to others who benefit from it.

Shiller's proposals in The New Financial Order were that these innovations should be made more accessible to retail buyers to give us the ability to hedge away our excessive exposure to housing market fluctuations, trade cycles, and the risk that the industry we've accumulated a lifetime of experience in will go the way of the buggy whip. Specifically focusing on real estate, Shiller noted that while most home buyers benefit from the long-term increase in home values, a significant number of people are hurt when prices fall for short periods of times or in particular locations. Most of us would benefit by selling off a little of the upside exposure in exchange for some down-side protection.

Shiller has focused some of his effort recently in finding ways to make these kinds of markets more likely and more accessible. The introduction of housing price indexes this year at CME and HedgeStreet, among other places, is possible because Shiller helped develop reliable indexes that major players in the real estate market agree are representative of actual price changes over time. The market in these securities isn't yet liquid enough for it to make sense for an average home owner to trade away their specific exposure. Besides the markets are unfamiliar enough that few would find the markets.

The new products that the Economist talked about are designed to bridge this gap. The right time to talk to home buyers about their risks and to get them to think about the trade-offs is when they're buying or refinancing. The new products are a kind of mortgage that links the value of the loan to regional housing prices. If the market falls locally, the bank forgives a chunk of the loan; if the market rises, the bank shares the gain. This seems ideal for potential buyers who are worried about the real estate bubble. And it seems perfectly reasonable for banks and home owners to share the risk; home owners are overexposed, and banks underexposed to residential real estate. The banks are positioned to take advantage of the long term growth, and risk-averse home buyers can lay off some of their risk without giving up all chance of winning through appreciation. So far, these products are not available in the US. OTOH, according to the Economist, British home buyers aren't taking banks up on the offer yet.

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