Stephen Goldup/Univ. of Edinburgh

TAMING CHANCE. This molecule acts like the microscopic demons James Clerk Maxwell envisaged in the 19th century. Thermal or Brownian motion moves a ring-shaped molecule (blue) from one side to another of a dumbbell-shaped molecule (yellow). But a “gate” molecule (green) is designed to lock the ring molecule to just one side of the dumbbell. Brownian motion provides energy to move the ring, but the gate molecule steers it.

Occasionally, scientists stumble upon what seems to be a free lunch. But they’re not concerned about possibly violating the laws of economics. It would be much more shocking to break the laws of physics.

To physicists, the no-free-lunch rule is precious. One form of it is the first law of thermodynamics, which says that energy cannot be created from nothing. The second law of thermodynamics goes even further, declaring not only that lunches are never free but also that they come at some minimum price.

Nonetheless, some natural phenomena seem, at first glance, to violate the spirit, if not the letter, of those laws. Take living cells. In recent years, scientists have found that some molecular machines—proteins that perform crucial tasks of life, from shuttling molecules through membranes to reading information off of DNA—seem to move spontaneously. These machines are likely powered by the random motion of water molecules in their environment, the “thermal noise” that thermodynamics insists is not available for doing work.

While some researchers debate how such machines work without breaking physical laws, other scientists have begun to exploit similar phenomena to create artificial molecular motors—nanomachines that imitate nature by putting randomness to work. “The idea is, let’s take advantage of thermal noise, rather than fight against it,” says Dean Astumian, a theoretical chemist at the University of Maine in Orono.

Researchers have just begun to build artificial nanomachines that perform simple tasks, such as moving molecules, by steering random motion in one direction rather than another. In the Feb. 13 Journal of the American Chemical Society, a team led by David Leigh, a chemist at the University of Edinburgh in Scotland, describes the first molecule designed to use chemical energy to open or close a gate and allow one of its parts to randomly cross the gate in one direction, but not the other.

It’s very much like the task assigned to a hypothetical “demon” by the 19th-century Scottish physicist James Clerk Maxwell. His thought experiment was an early attempt to show how the second law defines group behavior and thus applies only to large numbers of particles.

(Read the rest of this article for free on the Web site of Science News.)

The Archimedes Codex: How a Medieval Prayer Book Is Revealing the True Genius of Antiquity’s Greatest Scientist — Reviel Netz and William Noel

Some of the works of Archimedes—the Greek thinker and tinkerer who lived in 3rd-century B.C. Sicily and discovered the principle of buoyancy—survive only in a single 8th-century copy. As Netz and Noel recount, the manuscript was lost and found multiple times, erased and recycled into a prayer book by a 13th-century monk, and lived through fire, mold, and forgers who covered some of its pages with fake medieval paintings. In 1998, a collector bought the manuscript for $2 million and entrusted it to Noel, a curator at the Walters Art Museum in Baltimore. Using pioneering technology, researchers have managed to read most of the book’s content, allowing historians—including Netz—new glimpses into Archimedes’ genius. Da Capo, 2007, 320 p., color photos and b&w illus., hardcover, $27.50. [Also see: The 'Jurassic Park' of Manuscripts.]

ISBN: 030681580X

Apollo’s Fire: Igniting America’s Clean Energy Economy — Jay Inslee and Bracken Hendricks

The authors present a manifesto for the Apollo Alliance, a clean-energy advocacy organization that Inslee, a [democratic] congressman from Washington state, helped found and where Hendricks is a senior fellow. Greening the U.S. economy is not only necessary to save the environment and wean us off Middle Eastern oil, the authors write. It will also create millions of “green-collar” jobs, which will be held by everyone from engineers developing better solar panels to the workers who will install them. The book evokes the national focus on reaching the moon in the 1960s to advocate a comprehensive array of policy and technological solutions. It also aims to allay fears of losing jobs to new regulations and to defuse tensions between trade unions and environmentalists, two traditionally Democratic constituencies. Island Press, 2007, 416 p., b&w photos, hardcover, $25.95.

ISBN: 1597261750

Four Laws That Drive the Universe — Peter Atkins

Although it deals with seemingly familiar concepts such as temperature, thermodynamics ranks among the most conceptually treacherous branches of physics. Many students, for example, have puzzled over the definition of entropy, a measure of disorder. Atkins, a chemistry professor at the University of Oxford in England, guides the reader through the basics of thermodynamics in just over 120 pages by keeping a steady focus on the subject’s four fundamental laws. The book contains a modicum of formulas. And although it’s tersely written and titled like a popular-science book, Four Laws is a textbook both in essence and in structure. Atkins’ elegant exposition will appeal to the lay reader with a serious interest in physics. Oxford Univ. Press, 2007, 128 p., b&w illus., hardcover, $19.95.

ISBN: 0199232369

Auto Mania: Cars, Consumers, and the Environment — Tom McCarthy

As crude oil approaches $100 per barrel, wallet pain, more than any fears of global warming, may eventually lead Americans to reconsider their thirst for ever-heavier and ever-faster cars and trucks. Since Henry Ford’s invention of the mass-produced car, consumers have chosen what to drive based less on the environmental consequences—which include not just tailpipe emissions but the full product cycle, from mining to disposal—than on the allure of the car as a status symbol, McCarthy argues. He tells the story of a nation’s affair with four wheels and of how the car’s role as cultural icon has influenced its evolution. When considering the car’s impact on the environment, it is simplistic to blame it all on Detroit’s “big three” or the inadequacy of government regulations. One case in point, McCarthy writes, is the astonishing rise of the SUV, which took even car manufacturers by surprise. Yale Univ. Press, 2007, 368 p., b&w illus. and photos, hardcover, $32.50.

ISBN: 0300110383

Now, scientists think they may have found out how and why things find their way into knotty arrangements. By tumbling a string of rope inside a box, biophysicists Dorian Raymer and Douglas Smith have discovered that knots—even complex knots—form surprisingly fast and often. The string first coils up, and then its free ends swivel around the other coils, tracing a random path among them. That essentially makes the coils into a braid, producing knots, the scientists say.

The results’ relevance may go well beyond explaining the epidemic of tangled venetian blind cords. That’s because spontaneous knots seem to be prevalent in nature, especially in biological molecules. For example, knottiness may be crucial to the workings of certain proteins (see “Knots in Proteins”). And knots can randomly form in DNA, hampering duplication or gene expression—so much so that living cells deploy special knot-chopping enzymes.

(Read the rest of this article for free on the Web site of Science News.)

The new technique for creating such “rogue waves” in the lab might help physicists understand them as a general phenomenon, in the hope of predicting the risks for vessels at sea.

A rogue wave will appear “at a random location, at a random time,” says Bahram Jalali, an electrical engineer at the University of California, Los Angeles (UCLA), who developed an interest in rogue waves while spending time on his 36-foot sailboat.

(Read the rest of my article on the Science News web site (password required))

Cover illustration by Anders Sandberg

This artist’s impression represents a view of a hyperbolic plane — the kind of beast that M. C. Escher loved to paint — projected on the surface of a sphere. Maldacena’s concept of the holographic universe translates a string theory living in hyperbolic space (the 3-D analogue of hyperbolic plane) into a theory of particles living on the surface of a sphere.

In a school of thought that teaches the existence of extra dimensions, Juan Maldacena may at first sound a little out of place.

String theory is physicists’ still-tentative strategy for reconciling Einstein’s theory of gravitation with quantum physics. Its premise is that the subatomic particles that roam our three-dimensional world are really infinitesimally thin strings vibrating in nine dimensions. According to Maldacena, however, the key to understanding string theory is not to add more dimensions but to cut their number down.

In his vision, the mathematical machinery of strings completely translates into a more ordinary quantum theory of particles, but one whose particles would live in a universe without gravity. Gravity would be replaced by forces similar to the nuclear forces that prevailed in the universe’s first instants. And this would be a universe with fewer dimensions than the realm inhabited by strings.

Just as a hologram creates the illusion of the third dimension by scattering light off a 2-D surface, gravity and the however many dimensions of space could be a higher-dimensional projection of a drama playing out in a flatter world.

How many dimensions space has could all be a matter of perspective.

(This article checks out the state of Maldacena’s conjecture ten years after he first proposed it, in November 1997. Read the rest of it on the Science News web site)

In many ecosystems, several competing species coexist because none is best at everything. Tobias Reichenbach of the Ludwig Maximilian University in Munich and his colleagues ran computer simulations of three virtual bacteria species fighting a sort of rock-paper-scissors game.

One species produces a toxin. A second is immune to the toxin and outcompetes the first. A third species is sensitive to the toxin but can overtake the second species because it’s unburdened by the metabolic cost of producing an antidote. Each virtual population, shown here in a different color, propagates in waves as it pushes aside its weaker competitor while being chased by the stronger one, the researchers explain in an upcoming Physical Review Letters. Scientists have observed similar patterns among certain marine organisms.

Tobias Reichenbach

(From Science News, Nov. 3, 2007.)

Now, astrophysicists may have to rethink their models of how supernovae create heavier elements. On the other hand, they may also be able to explain anomalous X-ray flashes coming from neutron stars. When matter falls onto a neutron star and starts sinking into its crust, pressures 10 trillion times as high as those at the sun’s center force electrons and protons to merge, forming neutrons. Aluminum-42 and magnesium-40 may be among the elements that form temporarily during that process.

Read my article from this week’s Science News

Washed away

Last year, physicists reported seeing tantalizing experimental traces of the axion, a hypothetical subatomic particle that’s been mentioned as a possible constituent of cosmic dark matter. But the axion was showing up where theory said it shouldn’t be. It now looks as if it wasn’t there after all.

The particle sprang from an attempt to explain certain differences between the strong and weak nuclear forces. Cosmologists seized on the axion because its properties made it a plausible component of dark matter, the unseen material that far outweighs ordinary matter in the universe.

Read the rest of my article, freely available on the Science News Web site.

As I recounted in my end-of-year special last year, MIT physicist Frank Wilczek called the particle after a brand of detergent, because it was supposed to wash away all of the problems of the so-called standard model of particle physics. The brand is not longer sold in the U.S., but it apparently still is in France.

In the latest experiment, researchers attempted to demonstrate the axion’s existence by looking for an effect known as photon regeneration, or, in Zenlike fashion, as “light shining through a wall.” As I write in this week’s Science News:

Researchers shoot a laser beam through a magnetic field toward a metal plate. The metal wall blocks photons, but any axions created in the field would pass through. On the other side of the wall lies a second magnetic field that would convert some of the axions back into photons, making it appear that some photons had passed through.

They detected no axions at all. However, physicists say other types of experiment might have a better chance at discovering the particle. The most intriguing one would look for “light shining through the sun.” As the sun passes in front of a source of gamma rays located far away in the universe, some of the source’s photons could turn into axions. Those would easily zip through the sun, and then perhaps convert back into gamma ray photons, wihch astrophysicists could then pick up.

Wilczek told me that he has kept a box of the U.S.-brand detergent in his basement. Perhaps, if one day the axion is discovered, he could make loads of money by selling it on eBay.

“Graphene has always been before our eyes, but no one ever tried to look,” says Andre Geim, a physicist at the University of Manchester in England. A single-atom-thick, chicken wire web of carbon atoms, graphene forms the layers that stack up to make the graphite found in pencil lead and carbon soot.

However mundane the stuff may be, physicists have long predicted that if it were possible to isolate single graphene sheets, they would be sturdier than diamond and would have almost preternatural abilities to manipulate electrons. That could make graphene a better material than silicon for making computer chips. Until recently, though, no one had been able to isolate graphene sheets, let alone do anything useful with them.

In 2004, Geim and his collaborators startled the physics community by announcing that they had peeled graphene layers off graphite using common adhesive tape. The discovery raised a buzz in physics circles reminiscent of the excitement that greeted carbon nanotubes a decade ago.

Read the rest of my cover story, freely available on the Science News web site.

While calling NASA’s “manned” space flight programs (such as [the International] Space Station) worthless with regards to science, Steven Weinberg calls NASA’s “unmanned” space flight programs (such as Martian robots Spirit and Opportunity robots and Hubble Telescope) very important to the advancement of science.

Steven Weinberg stated at the Tuesday, September 18, 2007 Science Writers’ Workshop called “Dark Energy: A Decade of Discovery and Mystery” at the Space Telescope Science Institute [home of the Hubble Space Telescope] in Baltimore, Maryland, U.S.A., “The International Space Station is an orbital turkey. No important science has come out of it. I could almost say no science has come out of it. And I would go beyond that and say that the whole manned spaceflight program, which is so enormously expensive, has produced nothing of scientific value.”

(From Nobel Laureate Weinberg calls space station an “orbital turkey”)