Monday, December 28, 2009

The Lithium Rush


In the Bolivian Andes lies a vast salt flat that may shape the future of transportation.

Nearly four kilometers above sea level in the Bolivian Andes lies the Salar de Uyuni, the world's largest salt flat. But there is more to this ­surreal, moonlike landscape than meets the eye. Flowing in salt-water ­channels beneath the surface is the world's largest supply of lithium--and, possibly, the future of transportation. Lithium is the key ingredient in the lithium-ion batteries that will power the electric vehicles that will soon be rolling off production lines worldwide. Demand for the metal is expected to double in the next 10 years, and Bolivia, with an untapped resource estimated at nine million tons by the U.S. Geological Survey, is being called a potential "Saudi Arabia of lithium."


The 10,000-square-kilometer Uyuni salt flat (salar in Spanish) extends to the horizon in all directions. These days it's a breeding ground for pink flamingos and a draw for curious tourists, but in prehistoric times it was once an immense lake. Water falling in the Andes still flows here, and as it works its way over volcanic rocks toward the salar, it picks up minerals, including magnesium and lithium. Baked by the sun, the water becomes a mineral-rich brine that flows under the salt desert's crusty surface.


Source: http://www.technologyreview.com/computing/24058/

Sunday, December 20, 2009

Sounds Heard: Peter Evans—Nature/Culture

Editor's Note: Follow the source to its original site and hear a track from Evans amazing double album.

Trying to describe Peter Evans's trumpet playing pretty quickly leaves you scraping the bottom of the superlative bin. To anyone who's seen him play, phrases that would otherwise sound like just more breathless, context-free hype ("the greatest trumpet player of our time," "superhuman") feel just about right, and yet they only capture part of what Evans, at the age of 28, has already accomplished. Taking off from the solo performance aesthetic of saxophonist Evan Parker, Peter Evans has devoted his early career to the cultivation and refinement of an exhaustive and totalizing virtuosity.

Nature/Culture, a new double-disc release on Parker's Psi label, offers some surprises though: in addition to the expected jaw-dropping technique, Evans proves to be an electronic musician of uncommon vision and restraint, and a first-rate composer. It makes no sense to pigeonhole him as some Steve Vai-esque technical freak of nature (comforting as that may be to the less gifted). Peter Evans is one of the best musicians of his generation, and Nature/Culture is both a summary and documentation of his achievements so far, as well as a rich, rewarding, and deeply musical album.

Technique as Technology

In classical performance practice, technique as it impacts a player's sound has developed towards a model of maximal tone, minimal noise. Key noise, breath noise, changes of bow direction or hand position, and any other audible evidence that behind the sound there's an actual human body are treated as technical problems. The ideal is the erasure of the body's "imprint" on the sound.

On Nature/Culture, Evans puts forward a powerful and possibility-rich inversion of this model: rather than suppressing noise, technique can be the ability to modulate the noise/tone balance with maximal range, variation, and subtlety. Not only are the noise artifacts of trumpet playing not de-emphasized, they're amplified, both literally (on disc 1, with the use of an additional microphone positioned by his head), and metaphorically. Evans's basic vocabulary ranges from angular post-bop lines to "traditional" extended techniques (multiphonics, circular breathing) to a collection of radically original timbres and gestures that hover in the ambiguous middle of the noise/tone continuum.

Evans's mastery of extended techniques on trumpet is complete and unprecedented. More astonishingly, it's also combinatorial—not only can he play pedal-tones on piccolo trumpet with total fluency, he can also flutter-tongue them. While circular breathing. For minutes at a time.

This level of technical craft allows Evans to completely transfigure his instrument, to denature and reconceive the trumpet from its basic physical and acoustic properties. Here is where he truly separates himself from the many of his peers in the free improvisation scene, as he's developed an integrated concept of performance that binds together his technical discoveries into a larger metaphorical framework. For Evans, the trumpet serves as a point of intersection between the human and the technological, and his treatment of the instrument (while allowing for references to historical styles) is primarily abstract and analytical. The trumpet, voice, and microphone are treated as equal partners, as if the metal tube of the instrument connected smoothly to the flesh tube of the vocal tract through a composite vibrating membrane of lips and mouthpiece. The larynx serves as an auxiliary oscillator that distorts or ring-modulates the sound when engaged. The valves of the trumpet are gates and switches that shorten and lengthen the overall circuit, redirecting signal flow. The microphone, most often inserted into the bell of the trumpet as a kind of paradoxical "amplifier mute," provides abrupt and vertiginous shifts in auditory perspective. In fact, one gets the impression that Evans has set up a sonic network of sufficient complexity that its response to an input is intentionally difficult to predict or control (especially when that input is often at the highest possible gain). For this reason, while his performative godfather is clearly Evan Parker, aesthetically he seems to be exploring territory first touched on by David Tudor's hardware feedback networks, in which a high-energy signal is sent through an intentionally labyrinthine circuit, with chaotic and unpredictable results. When, at a recent live solo performance, Evans played a piccolo trumpet through the mouthpiece of a C-trumpet into a microphone, this image took on an even more concrete and visible form.

As his aesthetic is already heavily indebted to electronic gestures and timbres, Evans's use of actual electronics is appropriately subtle— utensile rather than prosthetic. Nature/Culture is divided into a live disc recorded in one take and partitioned into tracks after the fact, and a studio album in which Evans exploits the compositional possibilities of recording technology. On five, the album’s only instance of overt studio manipulation—and one of Nature Culture's strongest tracks—overdubbing serves a dramatic, orchestrational function. Four-and-a-half minutes into the piece the sound of a bucket-muted trumpet suddenly bleeds out into a corona of duplicates, a Niblock-style drone-cloud that saturates the remainder of the ten-minute track without calling direct attention to the sudden flip into artificiality.

The lightness of his touch with electronic manipulation reinforces the sense that the technology itself is not quite the point. Technique is the real tool, and it's the imitation of technological processes and effects, rather than any specific hardware or software, that spurs him to extend the limits of the possible. The result is all the more impressive, and sidesteps the most common trap of the instruments-plus-electronics genre (chez Boulez, anyway): the moment anything is possible is the moment we stop caring. Struggle, fallibility, and risk have to be part of the equation.

Performance as Practice

Watching Evans perform live, it's clear that, for all his monstrous prowess on the trumpet, he still insists on playing at the absolute limit of his own technique. His virtuosity isn't of the sweat-less, no-hair-out-of-place variety; rather, he's always stretching to go a little further, to add one more layer, to avoid repeating himself (though like any seasoned improviser he has a set of go-to gestures and finger patterns).

When pursued with this degree of dedication and restless intensity, the act of performance becomes a kind of practice, an inexhaustible "path" that offers an image of perfection and a series of concrete steps that can be taken to approach it. Solo performance clarifies this dimension even further: there's no one else to blame if something goes wrong, no other artistic impulse with which to negotiate. For the performer, playing solo is an unmediated encounter with the self. In turn, solo free improvisation (especially on a monophonic instrument) escalates the terror-level of this encounter to its highest pitch. To watch someone overcome the implicit threat of this situation gives you a pleasure similar to watching great athletes succeed under tremendous pressure. You feel proud of your species.

Yet this kind of cultivation, in expanding the limits of the possible, also redefines what it means to be human. Evans's mastery of extended circular breathing subverts the periodic, breath-determined phrase length that serves as one of the basic, subconscious signs of humanness in music; this in turn allows him to deploy a truly electronic aesthetic as one of several stylistic poles in his solo performance. Thus what might seem at first to be a kind of macho gimmick turns out to be a crucial part of the music's deep structure—an aesthetic necessity that drives the technical innovation, rather than the reverse.

Nature/Culture

While the spastic energy of Evans live performances is inevitably somewhat muted on record, the first (studio) disc of Nature/Culture compensates with a fresh focus on composition and formal rigor. Several of the tracks stand on their own as coherent, inventive, and compelling pieces of music that reward repeated listening. the chamber, an 11-minute timbral study, focuses almost exclusively on the sound of multiphonics overdriving a bubble-shaped harmon mute. Evans's sense of pacing and proportion is mature and unhurried; at several points the music yawns into silence, and he seems perfectly comfortable allowing it the space to rest and breathe before resuming the thread. A similar degree of sensitivity enlivens Nature/Culture b, a kind of duet with controlled feedback, and the year's clear Grammy frontrunner in the "Best Use of Key Clicks/Valve Noise" category. full, an explosive piccolo trumpet freak-out, achieves an atomized, kaleidoscopic polyphony that's dazzling, overwhelming, and not a second too long. It's exactly the result the second-generation of New Complexity composers attempt to achieve again and again. That Peter Evans, simply by going about his artistic business, happens to viciously pwn this particular clique can only be another check in his column.

While Nature/Culture can't truly replace the experience of seeing Evans play live, as a document of a phenomenally gifted young player operating at the top of his game, it's tremendously rewarding. And inspiring, too: even as it deftly summarizes what Evans has already accomplished, it also shows him opening up new compositional, technical, and aesthetic possibilities for future exploration. The work isn't done yet, in other words. Though when you can do just about anything, "What next?" becomes a much more complicated question.












Source: http://www.newmusicbox.org/article.nmbx?id=6211

Wednesday, December 2, 2009

The Secrets Within Cosmic Dust


At the threshold of a sterile lab at NASA's Johnson Space Center in Houston, I pull on a white clean-room suit, a surgical cap and mask, booties and latex gloves. My host, a mineralogist named Mike Zolensky, swabs my digital voice recorder with alcohol to remove flakes of skin and pocket lint. He doesn't want any detritus to contaminate the precious dust in the room.

Once inside, Zolensky retrieves a palm-size glass box from a cabinet. The box holds a rectangular chunk, less than two inches across, of eerily translucent material. I lean in and squint at it but can't quite focus on anything. Zolensky turns off the lights and hands me a laser pointer. The red beam reveals thin streaks in the chunk that start at its surface and penetrate fractions of an inch, like the traces of tiny bullets. "Those are the comet impacts," he says. "It's beautiful to look at."

The tracks were made during the world's first—and only—attempt to chase a comet and bring a bit of it home. The NASA mission, called Stardust, sent a spacecraft to Comet Wild 2 (pronounced "VILT-too") on a seven-year journey that ended in 2006. It brought back the only material—other than moon rocks—taken directly from an extraterrestrial body.

Scientists expect the comet dust to yield clues about how our solar system and planet were formed. Earth has been through so much in its 4.5 billion years—volcanoes have erupted, mountains have risen and fallen, heat and water have chemically transformed rocks time and again—that scientists have trouble getting their hands on the earliest possible geologic evidence in what might be called showroom condition. It has all been buried or altered. In contrast, comets, which are about the same age as Earth, are pristine relics. "There's nothing left on Earth's surface that's nearly as old as these bits of crystals and minerals," says Carlton Allen, astromaterials curator at the Johnson Space Center. A comet, he continues, harbors the "starting material for our solar system, the stuff that came together to make everything we see."

Comets originated on the outskirts of a vast cloud of gas and dust that coalesced into our solar system more than 4.5 billion years ago. Crystals of ice far from the Sun gradually combined with dust to form trillions of comets, which have orbited slowly around the Sun ever since in a deep freeze far beyond Neptune. Only when gravity from a nearby star or some cosmic disturbance nudges them do they approach the Sun; then we see streams of gas and dust as the ice vaporizes—the signature tail.

The most famous, Comet Halley, is barely ten miles across, but it produces a beautiful tail tens of millions of miles long when its looping orbit brings it between Earth and the Sun every 76 years. (Earth will see it again in 2061.) Asteroids, too, are ancient, but most orbit between Mars and Jupiter, where the Sun has baked them for billions of years. Most of them are dense and rocky, some even metallic, shedding pieces that sometimes land on Earth as meteorites.

The travel plan of NASA's Stardust sounds like a Buck Rogers adventure. Swing far past Mars to within 150 miles of Comet Wild 2, which streaks by at 13,700 miles per hour. Catch fragments without destroying them. Travel back to Earth and drop a capsule into the atmosphere for a blazing nighttime re-entry over Utah. Parachute to the ground without crashing. "We were scared up to the last second," Zolensky says. "We still can't believe it really worked."

For all the impressive rocketry, the mission's most significant technology may have been the strange substance that caught the comet dust. Called aerogel, it's the lightest solid ever created. A slab the size of an average person would weigh less than a pound. A scientist once let me crumble some in my hand; it felt like brittle talc. Yet aerogel is tough. It's made of silica compounds arranged in an elaborate web that can snare particles plowing into it at up to six times the speed of a rifle bullet. The spacecraft carried two aluminum collecting trays shaped like oversize tennis rackets. Each tray held about 130 rectangular pockets filled with aerogel blocks smaller than ice cubes.

In the clean room, Zolensky returns the aerogel chunk to the storage cabinet and removes a bolted aluminum case. Inside lies an entire comet collection tray. It's worth about $200 million. "I'm always nervous about this part," he says. "I try not to drop it." He places the case on a stainless steel table, unbolts it and lifts the lid. "Air flows down from the ceiling, so the rule here is that we never stand over the tray," he tells me. Even with the mask on, I am acutely aware that I must not sneeze.

The aerogel cubes, tinged lu­minescent blue, look like puffs of breath exhaled on a winter morning and frozen solid. The laser pointer reveals scores of tracks marring the cubes' surfaces and interiors, some like sharp pinpricks, others like splaying roots.

A few dozen cubes are missing from the tray. Zolensky and his colleagues have cut out hundreds of small sections of those cubes. They remove an entire particle track by poking a pair of sharp glass fibers into the aerogel, a process that takes up to a day. The extracted piece looks like the clipped corner of a fingernail and has a particle at one end.

Seen through a microscope, the particle Zolensky shows me is jet black. Astronomers once pictured comets as gently disintegrating "fluffy ice balls." Then detailed photographs revealed that comets' outer rinds are blackened crusts, charred by the radiation of space. Ice and dust spew through fissures in the crust, eroding the comet's interior with each orbit. The Stardust samples—messengers from the inside of Wild 2—show that comets are dark through and through.

Under higher magnification, the dust particles look like exploded popcorn kernels. Stardust scientists were surprised to find that some of the comet's grains are made of minerals that form only at extremely high temperatures. It appears that these grains arose close to the Sun, inside the orbit of Mercury, in a blast furnace far removed from the calm, cold margins of the solar system where comets now drift.

No one had expected that the hot ingredients of the inner solar system mixed with the cold outer solar system billions of years ago. "It's a remarkable result," says planetary scientist Michael A'Hearn of the University of Maryland. "It's causing us to rethink how things got put together." It may mean that wind or radiation from the newborn Sun was stronger than expected, propelling the heat-forged grains deep into the solar system, where they merged with ices and frigid dust into comets.

The collection tray also captured evidence suggesting that comets may have helped seed life on Earth. NASA researchers found traces of glycine—one of the amino acids that make up the proteins in all living things—on the aluminum foil lining the sides of the aerogel cubes. The discovery, confirmed this past summer, suggests that comets contain some of life's basic molecules. Comets and meteorites colliding with the young Earth would have spread such compounds, possibly providing the ingredients for the Earth's first cells.

Stardust wasn't the only comet mission. NASA's Deep Impact spacecraft slammed a probe into Comet P9/Tem­pel 1 in 2005 and found that the crust was rigid but the layers underneath were weak and powdery. A European mission now en route, Rosetta, will try to land on a comet in 2014, scoop up some icy dirt and analyze it on the spot.

After we strip off our clean-room suits, Zolensky takes me downstairs to see the mission's return capsule. (It is now on display at the National Air and Space Museum.) The cone-shaped shield that protected Stardust's cargo during its fiery re-entry is about a yard wide. There's some dirt on it, Utah mud from the landing. The capsule's surface, a carbon composite mixed with cork, is burned and yields slightly to the touch. The spacecraft flew three billion miles—the most distant traveler ever to find its way home.

Source: http://www.smithsonianmag.com/science-nature/The-Secrets-Within-Cosmic-Dust.html