Sunday, April 29, 2012
Reading List: Manifold: Time
- Baxter, Stephen. Manifold: Time. New York: Del Rey, 2000. ISBN 978-0-345-43076-2.
- One claim frequently made by detractors of “hard” (scientifically realistic) science fiction is that the technical details crowd out character development and plot. While this may be the case for some exemplars of the genre, this magnificent novel, diamondoid in its science, is as compelling a page-turner as any thriller I've read in years, and is populated with characters who are simultaneously several sigma eccentric yet believable, who discover profound truths about themselves and each other as the story progresses. How hard the science? Well, this is a story in which quantum gravity, closed timelike curves, the transactional interpretation of quantum mechanics, strange matter, the bizarre asteroid 3753 Cruithne, cosmological natural selection, the doomsday argument, Wheeler-Feynman absorber theory, entrepreneurial asteroid mining, vacuum decay, the long-term prospects for intelligent life in an expanding universe, and sentient, genetically-modified cephalopods all play a part, with the underlying science pretty much correct, at least as far as we understand these sometimes murky areas. The novel, which was originally published in 2000, takes place in 2010 and subsequent years. NASA's human spaceflight program is grounded, and billionaire Reid Malenfant is ready to mount his own space program based on hand-me-down Shuttle hardware used to build a Big Dumb Booster with the capability to conduct an asteroid prospecting and proof-of-concept mining mission with a single launch from the private spaceport he has built in the Mojave desert. Naturally, NASA and the rest of the U.S. government is doing everything they can to obstruct him. Cornelius Taine, of the mysterious and reputedly flaky Eschatology, Inc., one of Malenfant's financial backers, comes to him with what may be evidence of “downstreamers”—intelligent beings in the distant future—attempting to communicate with humans in the present. Malenfant (who is given to such) veers off onto a tangent and re-purposes his asteroid mission to search for evidence of contact from the future. Meanwhile, the Earth is going progressively insane. Super-intelligent children are being born at random all around the world, able to intuitively solve problems which have defied researchers for centuries, and for some reason obsessed with the image of a blue disc. Fear of the “Carter catastrophe”, which predicts, based upon the Copernican principle and Bayesian inference, that human civilisation is likely to end in around 200 years, has uncorked all kinds of craziness ranging from apathy, hedonism, denial, suicide cults, religious revivals, and wars aimed at settling old scores before the clock runs out. Ultimately, the only way to falsify the doomsday argument is to demonstrate that humans did survive well into the future beyond it, and Malenfant's renegade mission becomes the focus of global attention, with all players attempting to spin its results, whatever they may be, in their own interest. This is a story which stretches from the present day to a future so remote and foreign to anything in our own experience that it is almost incomprehensible to us (and the characters through which we experience it) and across a potentially infinite landscape of parallel universes, in which intelligence is not an epiphenomenon emergent from the mindless interactions of particles and fields, but rather a central player in the unfolding of the cosmos. Perhaps the ultimate destiny of our species is to be eschatological engineers. That is, unless the squid get there first. Here you will experience the sense of wonder of the very best science fiction of past golden ages before everything became dark, claustrophobic, and inward-looking—highly recommended.
Monday, April 23, 2012
Reading List: The Omnivore's Dilemma
- Pollan, Michael. The Omnivore's Dilemma. New York: Penguin Press, 2006. ISBN 978-0-14-303858-0.
- One of the delights of operating this site is the opportunity to interact with visitors, whom I am persuaded are among the most interesting and informed of any audience on the Web. The feedback messages and book recommendations they send are often thought-provoking and sometimes enlightening. I don't know who I have to thank for recommending this book, but I am very grateful they took the time to do so, as it is a thoroughly fascinating look at the modern food chain in the developed world, and exploration of alternatives to it. The author begins with a look at the “industrial” food chain, which supplies the overwhelming majority of calories consumed on the planet today. Prior to the 20th century, agriculture was almost entirely powered by the Sun. It was sunlight that drove photosynthesis in plants, providing both plant crops and the feed for animals, including those used to pull ploughs and transport farm products to market. The invention of the Haber process in 1909 and its subsequent commercialisation on an industrial scale forever changed this. No longer were crop yields constrained by the amount of nitrogen which could be fixed from the air by bacteria symbiotic with the roots of legume crops, recycled onto fields in the manure and urine of animals, or harvested from the accumulated droppings birds in distant places, but rather able to be dramatically increased by the use of fertiliser whose origin traced back to the fossil fuel which provided the energy to create it. Further, fossil fuel insinuated itself into agriculture in other ways, with the tractor replacing the work of farm hands and draught animals; railroads, steam ships, trucks, and aircraft expanding the distance between production on a farm and consumption to the global scale; and innovations such as refrigeration increasing the time from harvest to use. All of these factors so conspired to benefit the species Zea mays (which Americans call “corn” and everybody else calls “maize”) that one could craft a dark but plausible science fiction story in which that species of grass, highly modified by selective breeding by indigenous populations in the New World, was actually the dominant species on Earth, having first motivated its modification from the ancestral form to a food plant ideally suited to human consumption, then encouraged its human servants to spread it around the world, develop artificial nutrients and pesticides to allow it to be grown in a vast monoculture, eradicating competitors in its path, and becoming so central to modern human nutrition that trying to eliminate it (or allowing a natural threat to befall it) would condemn billions of humans to starvation. Once you start to think this way, you'll never regard that weedless field of towering corn stretching off to the horizon in precisely the same way…. As the author follows the industrial food chain from a farm in the corn belt to the “wet mill” in which commodity corn is broken down into its molecular constituents and then reassembled into the components of processed food, and to the feedlot, where corn products are used to “finish” meat animals which evolved on a different continent from Zea mays and consequently require food additives and constant medication simply to metabolise this foreign substance, it becomes clear that maize is not a food, but rather a feedstock (indeed, the maize you buy in the supermarket to eat yourself is not this industrial product, but rather “sweet corn” produced entirely separately), just as petroleum is used in the plastics industry. Or the food industry—when you take into account fertiliser, farm machinery, and transportation, more than one calorie of fossil fuel is consumed to produce a calorie of food energy in maize. If only we could make Twinkies directly from crude oil…. All of this (and many things I've elided here in the interest of brevity [Hah! you say]) may persuade you to “go organic” and pay a bit more for those funky foods with the labels showing verdant crops basking in the Sun, contented cows munching grass in expansive fields, and chickens being chickens, scratching for bugs at liberty. If you're already buying these “organic” products and verging on the sin of smugness for doing so, this is not your book—or maybe it is. The author digs into the “industrial organic” state of the art and discovers that while there are certainly benefits to products labelled “organic” (no artificial fertilisers or pesticides, for example, which certainly benefit the land if not the product you buy), the U.S. Department of Agriculture (the villain throughout) has so watered down the definition of “organic” that most products with that designation come from “organic” factory farms, feedlots, and mass poultry confinement facilities. As usual, when the government gets involved, the whole thing is pretty much an enormous scam, which is ultimately damaging to those who are actually trying to provide products with a sustainable solar-powered food chain which respects the land and the nature of the animals living on it. In the second section of the book, the author explores this alternative by visiting Polyface Farms in Virginia, which practices “grass farming” and produces beef, pork, chickens and eggs, turkeys, rabbits, and forest products for its local market in Virginia. The Salatin family, who owns and operates the farm, views its pastures as a giant solar collector, turning incident sunlight along with water collected by the surrounding forest into calories which feed their animals. All of the animal by-products (even the viscera and blood of chickens slaughtered on site) are recycled into the land. The only outside inputs into the solar-powered cycle are purchased chicken feed, since grass, grubs, and bugs cannot supply adequate energy for the chickens. (OK, there are also inputs of fuel for farm machinery and electricity for refrigeration and processing, but since the pastures are never ploughed, these are minimal compared to a typical farm.) Polyface performs not only intensive agriculture, but what Salatin calls “management intensive” farming—an information age strategy informed by the traditional ecological balance between grassland, ruminants, and birds. The benefit is not just to the environment, but also in the marketplace. A small holding with only about 100 acres under cultivation is able to support an extended family, produce a variety of products, and by their quality attract customers willing to drive as far as 150 miles each way to buy them at prices well above those at the local supermarket. Anybody who worries about a possible collapse of the industrial food chain and has provided for that contingency by acquiring a plot of farm land well away from population centres will find much to ponder here. Remember, it isn't just about providing for your family and others on the farm: if you're providing food for your community, they're far more likely to come to your defence when the starving urban hordes come your way to plunder. Finally, the author seeks to shorten his personal food chain to the irreducible minimum by becoming a hunter-gatherer. Overcoming his blue state hoplophobia and handed down mycophobia, he sets out to hunt a feral pig in Sonoma County, California and gather wild mushrooms and herbs to accompany the meal. He even “harvests” cherries from a neighbour's tree overhanging a friend's property in Berkeley under the Roman doctrine of usufruct and makes bread leavened with yeast floating in the air around his house. In doing so, he discovers that there is something to what he had previously dismissed as purple prose in accounts of hunters, and that there is a special satisfaction and feeling of closing the circle in sharing a meal with friends in which every dish was directly obtained by them, individually or in collaboration. This exploration of food: its origins, its meaning to us, and its place in our contemporary civilisation, makes clear the many stark paradoxes of our present situation. It is abundantly clear that the industrial food chain is harmful to the land, unsustainable due to dependence on finite resources, cruel to animals caught up in it, and unhealthy in many ways to those who consume its products. And yet abandoning it in favour of any of the alternatives presented here would result in a global famine which would make the Irish, Ukrainian, and Chinese famines of the past barely a blip on the curve. Further, billions of the Earth's inhabitants today can only dream of the abundance, variety, and affordability (in terms of hours worked to provide one's food needs) of the developed world diet. And yet at the same time, when one looks at the epidemic of obesity, type 2 diabetes, and other metabolic disorders among corn-fed populations, you have to wonder whether Zea mays is already looking beyond us and plotting its next conquest.
Sunday, April 15, 2012
Reading List: Kill Shot
- Flynn, Vince. Kill Shot. New York: Atria Books, 2012. ISBN 978-1-4165-9520-5.
- This is the twelfth novel in the Mitch Rapp (warning—the article at this link contains minor spoilers) series, but chronologically is second in the saga, picking up a year after the events of American Assassin (December 2010). Mitch Rapp has hit his stride as the CIA's weapon of choice against the terror masters, operating alone with only the knowledge of a few people, dispatching his targets with head shots when they least expect it and, in doing so, beginning to sow terror among the terrorists. Rapp is in Paris to take out the visiting Libyan oil minister, who has been a conduit for funding terrorist attacks, including the Pan Am Flight 103 bombing which killed Rapp's college sweetheart and set him on the trajectory toward his current career—this time it's personal. The hit goes horribly wrong, leaving a trail of bodies and hundreds of cartridge casings in a posh hotel, with the potential of a disastrous public relations blowback for the CIA, and Rapp's superiors looking at prospects ranging from congressional hearings at best to time in Club Fed. Based on how things went down, Rapp becomes persuaded that he was set up and does not know who he can trust and lies low, while his bosses fear the worst: that their assassin has gone rogue. The profane and ruthless Stan Hurley, who trained Rapp and whose opinion of the “college boy” has matured from dislike to detestation and distrust, is dispatched to Paris to find out what happened, locate Rapp, and if necessary put an end to his career in the manner to which Hurley and his goons are accustomed. This is a satisfying thriller with plenty of twists and turns, interesting and often complicated characters, and a thoroughly satisfying conclusion. We see, especially in the interrogation of “Victor”, how far Rapp has come from his first days with Hurley, and that the tension between the two may have at its roots the fact that they are becoming more and more alike, a prospect Rapp finds repellent. Unlike American Assassin, which is firmly anchored in the chaos of early 1990s Beirut, apart from a few details (such as mobile telephones being novel and uncommon), the present novel could be set at almost any time since 1990—historical events play no part in the story. It's best to read American Assassin first, as it provides the back story on the characters and will provide more insight into their motivations, but this book works perfectly well as a stand-alone thriller should you prefer to start here.
Friday, April 13, 2012
Paleo Postings: Paleo diet and supplementsA reader inquires:
Shouldn't the Paleo Diet itself contain the all the (expensive?) vitamins and minerals that you list as your dietary supplements?Not necessarily. While it is true that one can certainly obtain most essential micronutrients from regular dietary intake, doing so requires substantial attention to detail that many people, including me, are not willing to expend the time to do. Then there are matters such as Vitamin D. Ancestral humans spent most of their time outdoors and most hunter/gatherers lived closer to the equator than the bulk of the human population does today. Consequently, they had no difficulty synthesising sufficient Vitamin D from sunlight on their skin. To avoid deficiencies, some foods in the West are “fortified” with Vitamin D, principally milk and breakfast cereal. But these are two of the food groups (dairy and grain) which do not meet the paleo guidelines, so without a supplement you're quite likely to be deficient (unless you spend a lot of time in the Sun around the year). A doctor in practice in California (!) said that she routinely tests her patients (who are not on any special diets) and finds about 40% are deficient in Vitamin D. I view paleo primarily as a way to avoid substances which ancestral humans did not consume to which natural selection cannot (by its very mechanism) adapt those older than the age of last reproduction. Given that there is substantial biochemical evidence that these foods (in particular grain, and especially wheat and derived products) are linked to a variety of late-onset diseases, this bolsters the evolutionary argument. The connection between the consumption of highly glycemic foods (sugars, processed flour, etc.) and insulin resistance, which leads to obesity and type 2 diabetes, is extremely persuasive. Note also that in the paleolithic, individuals who survived the very high rate of infant and child mortality (which persisted until the advent of modern medicine and public health measures) and managed to live to age 15 could expect to live a mean 39 years more, for a total mean lifespan from birth of 54 years. If you're a person today who hopes to enjoy a mean lifespan from birth of around 80 years, you become interested in things such as antioxidants, micronutrients which prevent loss of bone mass and calcification of soft tissues, and dietary components which reduce systemic inflammation, which can have a wide variety of deleterious consequences. It is possible to obtain these from diet (after all, the molecules in supplements are mostly extracted from vegetable sources), but it would be quite an effort to balance all of them. For example, you can get all of the zeaxanthin and lutein recommended to prevent or slow macular degeneration in the eye and the development of cataracts by eating a large spinach salad every day. But would you want to, and would you keep it up? It's a lot easier to take a pill and be sure (especially as most of these substances are water soluble and pose no risk of overdose).
Monday, April 9, 2012
Reading List: Ignition!
- Clark, John D. Ignition! New Brunswick, NJ: Rutgers University Press, 1972. ISBN 978-0-8135-0725-5.
This may be the funniest book about chemistry ever written.
age of science fiction,
one recurring theme was the search for a super
“rocket fuel” (with “fuel” used
to mean “propellant”) which would enable
the exploits depicted in the stories. In the years between
the end of World War II and the winding down of the great
space enterprise with the conclusion of the Apollo project,
a small band of researchers (no more than 200 in the U.S.,
of whom around fifty were lead scientists), many of whom had
grown up reading golden age science fiction, found themselves
tasked to make their boyhood dreams real—to discover
exotic propellants which would allow rockets to accomplish
missions envisioned not just by visionaries but also the
hard headed military men who, for the most part, paid the
Propulsion chemists are a rare and special breed. As Isaac Asimov (who worked with the author during World War II) writes in a short memoir at the start of the book:
Now, it is clear that anyone working with rocket fuels is outstandingly mad. I don't mean garden-variety crazy or merely raving lunatic. I mean a record-shattering exponent of far-out insanity.
There are, after all, some chemicals that explode shatteringly, some that flame ravenously, some that corrode hellishly, some that poison sneakily, and some that stink stenchily. As far as I know, though, only liquid rocket fuels have all these delightful properties combined into one delectable whole.
And yet amazingly, as head of propulsion research at the Naval Air Rocket Test Station and its successor organisation for seventeen years, the author not only managed to emerge with all of his limbs and digits intact, his laboratory never suffered a single time-lost mishap. This, despite routinely working with substances such as:
Chlorine trifluoride, ClF3, or “CTF” as the engineers insist on calling it, is a colorless gas, a greenish liquid, or a white solid. … It is also quite probably the most vigorous fluorinating agent in existence—much more vigorous than fluorine itself. … It is, of course, extremely toxic, but that's the least of the problem. It is hypergolic with every known fuel, and so rapidly hypergolic that no ignition delay has ever been measured. It is also hypergolic with such things as cloth, wood, and test engineers, not to mention asbestos, sand, and water—with which it reacts explosively. It can be kept in some of the ordinary structural metals—steel, copper, aluminum, etc.—because the formation of a thin film of insoluble metal fluoride which protects the bulk of the metal, just as the invisible coat of oxide on aluminum keeps it from burning up in the atmosphere. If, however, this coat is melted or scrubbed off, the operator is confronted with the problem of coping with a metal-fluorine fire. For dealing with this situation, I have always recommended a good pair of running shoes. (p. 73)
And ClF3 is pretty benign compared to some of the other dark corners of chemistry into which their research led them. There is extensive coverage of the quest for a high energy monopropellant, the discovery of which would greatly simplify the design of turbomachinery, injectors, and eliminate problems with differential thermal behaviour and mixture ratio over the operating range of an engine which used it. However, the author reminds us:
A monopropellant is a liquid which contains in itself both the fuel and the oxidizer…. But! Any intimate mixture of a fuel and an oxidizer is a potential explosive, and a molecule with one reducing (fuel) end and one oxidizing end, separated by a pair of firmly crossed fingers, is an invitation to disaster. (p. 10)
One gets an excellent sense of just how empirical all of this was. For example, in the quest for “exotic fuel” (which the author defines as “It's expensive, it's got boron in it, and it probably doesn't work.”), straightforward inorganic chemistry suggested that burning a borane with hydrazine, for example:
2B5H9 + 5N2H4 ⟶ 10BN + 19H2
would be a storable propellant with a specific impulse (Isp) of 326 seconds with a combustion chamber temperature of just 2000°K. But this reaction and the calculation of its performance assumes equilibrium conditions and, apart from a detonation (something else with which propulsion chemists are well acquainted), there are few environments as far from equilibrium as a rocket combustion chamber. In fact, when you try to fire these propellants in an engine, you discover the reaction products actually include elemental boron and ammonia, which result in disappointing performance. Check another one off the list.
Other promising propellants ran afoul of economic considerations and engineering constraints. The lithium, fluorine, and hydrogen tripropellant system has been measured (not theoretically calculated) to have a vacuum Isp of an astonishing 542 seconds at a chamber pressure of only 500 psi and temperature of 2200°K. (By comparison, the space shuttle main engine has a vacuum Isp of 452.3 sec. with a chamber pressure of 2994 psi and temperature of 3588°K; a nuclear thermal rocket would have an Isp in the 850–1000 sec. range. Recall that the relationship between Isp and mass ratio is exponential.) This level of engine performance makes a single stage to orbit vehicle not only feasible but relatively straightforward to engineer. Unfortunately, there is a catch or, to be precise, a list of catches. Lithium and fluorine are both relatively scarce and very expensive in the quantities which would be required to launch from the Earth's surface. They are also famously corrosive and toxic, and then you have to cope with designing an engine in which two of the propellants are cryogenic fluids and the third is a metal which is solid below 180°C. In the end, the performance (which is breathtaking for a chemical rocket) just isn't worth the aggravation.
In the final chapter, the author looks toward the future of liquid rocket propulsion and predicts, entirely correctly from a perspective four decades removed, that chemical propulsion was likely to continue to use the technologies upon which almost all rockets had settled by 1970: LOX/hydrocarbon for large first stages, LOX/LH2 for upper stages, and N2O4/hydrazine for storable missiles and in-space propulsion. In the end economics won out over the potential performance gains to be had from the exotic (and often far too exciting) propellants the author and his colleagues devoted their careers to exploring. He concludes as follows.
There appears to be little left to do in liquid propellant chemistry, and very few important developments to be anticipated. In short, we propellant chemists have worked ourselves out of a job. The heroic age is over.
But it was great fun while it lasted. (p. 192)
Now if you've decided that you just have to read this book and innocently click on the title above to buy a copy, you may be at as much risk of a heart attack as those toiling in the author's laboratory. This book has been out of print for decades and is considered such a classic, both for its unique coverage of the golden age of liquid propellant research, comprehensive description of the many avenues explored and eventually abandoned, hands-on chemist-to-chemist presentation of the motivation for projects and the adventures in synthesising and working with these frisky molecules, not to mention the often laugh out loud writing, that used copies, when they are available, sell for hundreds of dollars. As I am writing these remarks, seven copies are offered at Amazon at prices ranging from US$300–595. Now, this is a superb book, but it isn't that good!
If, however, you type the author's name and the title of the book into an Internet search engine, you will probably quickly come across a PDF edition consisting of scanned pages of the original book. I'm not going to link to it here, both because I don't link to works which violate copyright as a matter of principle and since my linking to a copy of the PDF edition might increase its visibility and risk of being taken down. I am not one of those people who believes “information wants to be free”, but I also doubt John Clark would have wanted his unique memoir and invaluable reference to be priced entirely beyond the means of the vast majority of those who would enjoy and be enlightened by reading it. In the case of “orphaned works”, I believe the moral situation is ambiguous (consider: if you do spend a fortune for a used copy of an out of print book, none of the proceeds benefit the author or publisher in any way). You make the call.
Monday, April 2, 2012
Reading List: The Incredible Attack Aircraft of the USS United States
- Zichek, Jared A. The Incredible Attack Aircraft of the USS United States, 1948–1949. Atglen, PA: Schiffer Publishing, 2009. ISBN 978-0-7643-3229-6.
- In the peacetime years between the end of World War II in 1945 and the outbreak of the Korean War in 1950 the United States Navy found itself in an existential conflict. The adversary was not a foreign fleet, but rather the newly-unified Department of Defense, to which it had been subordinated, and its new peer service, the United States Air Force, which argued that the advent of nuclear weapons and intercontinental strategic bombing had made the Navy's mission obsolete. The Operation Crossroads nuclear tests at Bikini Atoll in 1946 which had shown that a well-placed fission bomb could destroy an entire carrier battle group in close formation supported the Air Force's case that aircraft carriers were simply costly targets which would be destroyed in the first days of a general conflict. Further, in a world where the principal adversary, the Soviet Union, had neither a blue water navy nor a warm weather port from which to operate one, the probability that the U.S. Navy would be called upon to support amphibious landings comparable to those of World War II appeared unlikely. Faced with serious policy makers in positions of influence questioning the rationale for its very existence on anything like its current scale, advocates of the Navy saw seizing back part of the strategic bombardment mission from the Air Force as their salvation. This would require aircraft carriers much larger than any built before, carrier-based strategic bombers in the 100,000 pound class able to deliver the massive nuclear weapons of the epoch (10,000 pound bombs) with a combat radius of at least 1,700—ideally 2,000—miles. This led to the proposal for CVA-58, USS United States, a monster (by the standards of the time—contemporary supercarriers are larger still) flush deck carrier which would support these heavy strategic bombers and their escort craft. This ship would require aircraft like nothing in the naval inventory, and two “Outline Specifications” were issued to industry to solicit proposals for a “Carrier-Based Landplane”: the basic subsonic strategic bomber, and a “Long Range Special Attack airplane”, which required a supersonic dash to the target. (Note that when the latter specification was issued on August 24th, 1948, less than a year had elapsed since the first supersonic flight of the Bell X-1.) The Navy's requirements in these two specifications were not just ambitious, they were impossible given the propulsion technology of the time: the thrust and specific fuel consumption of available powerplants simply did not permit achieving all of the Navy's requirements. The designs proposed by contractors, presented in this book in exquisite detail, varied from the highly conventional, which straightforwardly conceded their shortcomings compared to what the Navy desired, to the downright bizarre (especially in the “Special Attack” category), with aircraft that look like a cross between something produced by the Lucasfilm model shop and the fleet of the Martian Air Force. Imagine a biplane that jettisons its top wing/fuel tank on the way to the target, after having been launched with a Fireball XL-5 like expendable trolley; a “parasitic” airplane which served as the horizontal stabiliser of a much larger craft outbound to the target, then separated and returned after dispatching the host to bomb them commies; or a convertible supersonic seaplane which could refuel from submarines on the way to the target. All of these and more are detailed in this superbly produced book which is virtually flawless in its editing and production values. Nothing at all came of all of this burst of enthusiasm and creativity. On April 23rd, 1949, the USS United States was cancelled, provoking the resignation of the Secretary of the Navy and the Revolt of the Admirals. The strategic nuclear mission was definitively won by the Air Force, which would retain their monopoly status until the Navy got back into the game with the Polaris missile submarines in the 1960s.