Tuesday, January 22, 2008

Could The Universe Be Tied Up With Cosmic String?

ScienceDaily (Jan. 21, 2008) — A team of physicists and astronomers from the University of Sussex and Imperial College London have uncovered hints that there may be cosmic strings - lines of pure mass-energy - stretching across the entire Universe.

Cosmic strings are predicted by high energy physics theories, including superstring theory. This is based on the idea that particles are not just little points, but tiny vibrating bits of string Cosmic strings are predicted to have extraordinary amounts of mass - perhaps as much as the mass of the Sun - packed into each metre of a tube whose width is less a billion billionth of the size of an atom.

Lead researcher Dr Mark Hindmarsh, Reader in Physics at the University of Sussex, said: “This is an exciting result for physicists. Cosmic strings are relics of the very early Universe and signposts that would help construct a theory of all forces and particles.”

His team took data from NASA's Wilkinson Microwave Anisotropy Probe (WMAP), which is a satellite currently mapping the intensity of cosmic microwaves from all directions, and carefully compared the predictions of what should be seen with and without strings.

Dr Hindmarsh said: “We cannot yet see these strings directly. They are many billion light years away. We can only look for indirect evidence of their existence through precision measurements of the cosmic microwave background, of cosmic rays, gravitational radiation, and looking for double images of distant quasars.”

The four-person team are members of COSMOS, the UK's world-leading cosmology supercomputing consortium fronted by Stephen Hawking. Using a Silicon Graphics supercomputer they made predictions of how the strings would affect the Cosmic Microwave Background, relic radio waves from the Big Bang which fill the universe. It turned out that the best explanation for the pattern of this radiation was a theory which included strings.

Dr Hindmarsh said that better data is required before the existence of cosmic strings can be confirmed. He hopes this will be produced by the European Space Agency's Planck Satellite mission (due for launch this year).

The results are published in Physical Review Letters on 18 January, 2008.

Adapted from materials provided by University of Sussex, via AlphaGalileo.

Thursday, January 17, 2008

'Darkest ever' material created

By Helen Briggs
BBC News science reporter


The "darkest ever" substance known to science has been made in a US laboratory.

The material was created from carbon nanotubes - sheets of carbon just one atom thick rolled up into cylinders.

Researchers say it is the closest thing yet to the ideal black material, which absorbs light perfectly at all angles and over all wavelengths.

The discovery is expected to have applications in the fields of electronics and solar energy.

Theoretical clues

An ideal black object absorbs all the colours of light and reflects none of them. In theory, it should be possible to make something that approaches the "perfect absorber".

They've made the blackest material known to science
Prof Sir John Pendry

But it has proved difficult to construct an object that does not reflect light at all.

Researchers at Rensselaer Polytechnic Institute in Troy, New York, turned to carbon nanotubes - structures made from carbon, billionths of a metre across, that have unique properties.

Theory suggests that nanotubes might make a super black object, and experts are just starting to test these predictions.

A team led by Dr Pulickel Ajayan, who is presently at Rice University in Houston, Texas, built an array of vertically aligned, low-density carbon nanotubes. Dr Shawn Lin measured the optical properties.

The roughness of the material's surface was tuned to minimise its optical reflectance.



Experiments showed that this "forest" of carbon nanotubes was very good at absorbing light, and very poor at reflecting it.

Reporting their findings in the journal Nano Letters, Dr Ajayan, Dr Lin and colleagues say the reflectance of the material is three times lower than previously achieved.

This makes it the "darkest man-made material ever".

"The periodic nanotube structures make an ideal candidate for creating superdark materials, because it allows one to tailor light absorption by controlling the dimensions and periodicities of nanotubes in the structure," said Dr Ajayan.

Commenting on the study, Professor Sir John Pendry, who first predicted that such a discovery might be possible, said the results were promising.

"They've made the blackest material known to science," the theoretical physicist from Imperial College, London, told BBC News.

"The application will be to things like more efficient solar cells, more efficient solar panels and any application where you need to harvest light," he added.

Wednesday, January 16, 2008

World Bank Disgrace

From: http://online.wsj.com/article/SB120026972002987225.html?mod=opinion_main_review_and_outlooks


Credit Robert Zoellick for knowing how to put the best face on a profound embarrassment. On Friday, the World Bank president announced in a press release that the bank had "joined forces" with the government of India to "fight fraud and corruption" in that country's health sector. This is happening at the same time that Mr. Zoellick's colleagues are hounding bank anticorruption chief Suzanne Rich Folsom, the person primarily responsible for bringing the scandals to light.

Corruption is an endemic problem in bank projects, swallowing unknown but significant chunks from its $30 billion-plus annual portfolio. No less a problem has been the bank staff's ferocious resistance to anything that might stand in the way of its lending ever more money to projects run by the same governments that tolerate this malfeasance.


Yet nothing we've seen so far can compare to what has now been uncovered about five health projects in India, involving $569 million in loans. The projects were the subject of a "Detailed Implementation Review," a lengthy forensic examination undertaken by Ms. Folsom's Department of Institutional Integrity, known within the bank as INT. As of this writing the bank has not publicly released the review, though it's been shared with the bank's board. But we've seen a copy and are posting its executive summary on wsj.com/opinion and OpinionJournal.com (click here to see it). We are also posting photographs that show the real price that corruption in bank projects exacts on the poor. Here are some of the lowlights:

In the $54 million "Food and Drug Capacity Building Project," for which money is still being disbursed, the INT found "questionable procurement practices, some of which indicate fraud and corruption, in contracts representing 87 percent of the number of pieces and 88 percent of the total value of equipment procured." That is nearly $9 of every $10 in aid funds.

For the $194 million "Second National AIDS Control Project," the INT discovered that "some of the test kits supplied by particular companies often performed poorly by producing erroneous or invalid results, potentially resulting in the further spread of disease."

In the $114 million "Malaria Control Project," the review found "numerous indicators of poor product quality in the bed nets supplied by the firms." And in the $125 million "Tuberculosis Control Project," the INT discovered "bidders sharing the same address and telephone numbers, unit prices showing a common formula, and indicators of intent to split contract awards among several bidders."

After visiting 55 hospitals connected to the bank's $82 million "Orissa Health Systems Development Project" (Orissa is one of India's poorest states), INT investigators found "uninitiated and uncompleted work, severely leaking roofs, crumbling ceilings, molding walls, and non-functional water, sewage, and/or electrical systems." It also found "neonatal equipment that lacked adequate electrical grounding, potentially exposing babies and their medical staff to electrical shocks."

All this would be bad enough if Indian companies or officials were making off with ill-gotten gains behind the backs of World Bank staff. Instead, the INT found evidence of the bank repeatedly looking the other way. In the case of Orissa's 55 "hospitals," the INT found that the "construction management consultants (CMCs) who supervised the work certified that 38 of these hospitals to be complete to project specifications." In the AIDS Control Project, "the bank appeared to pay scant attention to the performance and quality of the goods supplied to the blood banks and testing centers, instead focusing on the number of such facilities being erected."

The report goes on in this vein for hundreds of pages. With the exception of Paul Volcker's investigation of the U.N. Oil for Food scandal, we can think of no comparable review of an international organization that has brought such damaging facts to light, certainly not one that was internally conducted.

Yet not only does Mr. Zoellick's press release fail to praise INT's dogged achievement, it ignores Ms. Folsom altogether. It does, however, give pride of place to bank managing director Ngozi Okonjo-Iweala, who was recently hired by Mr. Zoellick and is quoted as saying she is encouraged by the Indian government's "strong resolve" to deal with corruption.

We'll believe that resolve when we see it. Such promises would be more credible if Mr. Zoellick took meaningful steps to hold accountable those in the bank who acquiesce in this corruption. Former President Paul Wolfowitz showed real spine when he stopped lending to a related Indian health project after a previous INT investigation uncovered fraud. Yet lending to Indian health projects resumed the moment he departed last year.

We wonder, for example, what this now-documented Indian corruption means for the career of Praful Patel, who has been running the bank's South Asia operations since 2003, and for Managing Director Graeme Wheeler, who until recently oversaw Mr. Patel's work. Instead of accountability for these supervisors, the bank offers up the Orwellian contrivance by which Ms. Folsom has been whited-out from this story, like the proverbial vanishing commissar.

The foreign aid lobby sometimes says that corruption is the inevitable price of "doing good" in the developing world. Our online readers should look at the photographs of hazardous laboratories and sewage overflowing in hospitals, and wonder how anyone can make that case with a clear conscience.

Friday, January 11, 2008

Hubble finds double Einstein Ring

By http://www.spacetelescope.org/news/html/heic0803.html

10-Jan-2008: The NASA/ESA Hubble Space Telescope has revealed a never-before-seen optical alignment in space: a pair of glowing rings, one nestled inside the other like a bull's-eye pattern. The double-ring pattern is caused by the complex bending of light from two distant galaxies strung directly behind a foreground massive galaxy, like three beads on a string.

More than just a novelty, a very rare phenomenon found with the Hubble Space Telescope can offer insight into dark matter, dark energy, the nature of distant galaxies, and even the curvature of the Universe. A double Einstein ring has been found by an international team of astronomers led by Raphael Gavazzi and Tommaso Treu of the University of California, Santa Barbara. The discovery is part of the ongoing Sloan Lens Advanced Camera for Surveys (SLACS) program. They are reporting their results at the 211th meeting of the American Astronomical Society in Austin, Texas, USA. A paper has been submitted to The Astrophysical Journal.

The phenomenon, called gravitational lensing, occurs when a massive galaxy in the foreground bends the light rays from a distant galaxy behind it, in much the same way as a magnifying glass would. When both galaxies are exactly lined up, the light forms a circle, called an “Einstein ring”, around the foreground galaxy. If another more distant galaxy lies precisely on the same sightline, a second, larger ring will appear.

The odds of seeing such a special alignment are so small that Tommaso says that they “hit the jackpot” with this discovery.

Such stunning cosmic coincidences reveal so much about nature. Dark matter is not hidden to lensing,” added Leonidas Moustakas of the Jet Propulsion Laboratory in Pasadena, California, USA. “The elegance of this lens is trumped only by the secrets of nature that it reveals.

The massive foreground galaxy is almost perfectly aligned in the sky with two background galaxies at different distances. The foreground galaxy is 3 billion light-years away. The inner ring and outer ring are comprised of multiple images of two galaxies at a distance of 6 billion and approximately 11 billion light-years.

SLACS team member Adam Bolton of the University of Hawaii's Institute for Astronomy in Honolulu first identified the lens in the Sloan Digital Sky Survey (SDSS). “The original signature that led us to this discovery was a mere 500 photons (particles of light) hidden among 500,000 other photons in the SDSS spectrum of the foreground galaxy,” commented Bolton.

The twin rings were clearly visible in the Hubble image”, added Tommaso. “When I first saw it I said ‘wow, this is insane!’ I could not believe it!

The distribution of dark matter in the foreground galaxies that is warping space to create the gravitational lens can be precisely mapped. In addition, the geometry of the two Einstein rings allowed the team to measure the mass of the middle galaxy precisely to be a value of 1 billion solar masses. The team reports that this is the first measurement of the mass of a dwarf galaxy at cosmological distance (redshift of z=0.6).

A sample of several dozen double rings such as this one would offer a purely independent measure. The comparative radius of the rings could also be used to provide an independent measure of the curvature of space by gravity.

Observations of the cosmic microwave background (a relic from the Big Bang) favour flat geometry. A sample of 50 suitable double Einstein rings would be sufficient to measure the dark matter content of the Universe and the equation of state of the dark energy (a measure of its pressure) to 10 percent precision. Other double Einstein rings could be found with wide-field space telescope sky surveys that are being proposed for the Joint Dark Energy Mission (JDEM) and recently recommended by the National Research Council.

Wednesday, January 9, 2008

Time Travel in the Brain

By DANIEL GILBERT, RANDY BUCKNER


What are you doing when you aren't doing anything at all? If you said "nothing," then you have just passed a test in logic and flunked a test in neuroscience. When people perform mental tasks--adding numbers, comparing shapes, identifying faces--different areas of their brains become active, and brain scans show these active areas as brightly colored squares on an otherwise dull gray background. But researchers have recently discovered that when these areas of our brains light up, other areas go dark. This dark network (which comprises regions in the frontal, parietal and medial temporal lobes) is off when we seem to be on, and on when we seem to be off. If you climbed into an MRI machine and lay there quietly, waiting for instructions from a technician, the dark network would be as active as a beehive. But the moment your instructions arrived and your task began, the bees would freeze and the network would fall silent. When we appear to be doing nothing, we are clearly doing something. But what?


The answer, it seems, is time travel.

The human body moves forward in time at the rate of one second per second whether we like it or not. But the human mind can move through time in any direction and at any speed it chooses. Our ability to close our eyes and imagine the pleasures of Super Bowl Sunday or remember the excesses of New Year's Eve is a fairly recent evolutionary development, and our talent for doing this is unparalleled in the animal kingdom. We are a race of time travelers, unfettered by chronology and capable of visiting the future or revisiting the past whenever we wish. If our neural time machines are damaged by illness, age or accident, we may become trapped in the present. Alzheimer's disease, for instance, specifically attacks the dark network, stranding many of its victims in an endless now, unable to remember their yesterdays or envision their tomorrows.

Why did evolution design our brains to go wandering in time? Perhaps it's because an experience is a terrible thing to waste. Moving around in the world exposes organisms to danger, so as a rule they should have as few experiences as possible and learn as much from each as they can. Although some of life's lessons are learned in the moment ("Don't touch a hot stove"), others become apparent only after the fact ("Now I see why she was upset. I should have said something about her new dress"). Time travel allows us to pay for an experience once and then have it again and again at no additional charge, learning new lessons with each repetition. When we are busy having experiences--herding children, signing checks, battling traffic--the dark network is silent, but as soon as those experiences are over, the network is awakened, and we begin moving across the landscape of our history to see what we can learn--for free.


Animals learn by trial and error, and the smarter they are, the fewer trials they need. Traveling backward buys us many trials for the price of one, but traveling forward allows us to dispense with trials entirely. Just as pilots practice flying in flight simulators, the rest of us practice living in life simulators, and our ability to simulate future courses of action and preview their consequences enables us to learn from mistakes without making them. We don't need to bake a liver cupcake to find out that it is a stunningly bad idea; simply imagining it is punishment enough. The same is true for insulting the boss and misplacing the children. We may not heed the warnings that prospection provides, but at least we aren't surprised when we wake up with a hangover or when our waists and our inseams swap sizes. The dark network allows us to visit the future, but not just any future. When we contemplate futures that don't include us--Will the NASDAQ be up next week? Will Hillary run in 2008?--the dark network is quiet. Only when we move ourselves through time does it come alive.

Perhaps the most startling fact about the dark network isn't what it does but how often it does it. Neuroscientists refer to it as the brain's default mode, which is to say that we spend more of our time away from the present than in it. People typically overestimate how often they are in the moment because they rarely take notice when they take leave. It is only when the environment demands our attention--a dog barks, a child cries, a telephone rings--that our mental time machines switch themselves off and deposit us with a bump in the here and now. We stay just long enough to take a message and then we slip off again to the land of Elsewhen, our dark networks awash in light.

Gilbert and Buckner are professors of psychology at Harvard. Gilbert's Stumbling on Happiness was published last May.

Tuesday, January 8, 2008

U.S. Demand for Human Hair Grows, Used in Wigs, Pizza

Associated Press

FLORIDA CITY, Fla. — Walking into the small Florida City warehouse, Blair Blacker pauses to survey the towering pyramid of canvas bundles, each about the size of a punching bag, that contain the stock-in-trade of his business: human hair.

About 15 tons of it on a recent day, imported from China, neatly pressed into mats and ready to ship to farmers and nursery growers who swear by the horticultural benefits of Blacker's hairy wares.

"If you had told me when I was flying combat helicopters in Vietnam that one day I'd be sitting on 30,000 pounds of human hair," said Blacker, a retired Army colonel-turned-entrepreneur, "I'd have said you were crazy."


The mats stored in southern Miami-Dade County are part of a world marketplace for human hair. Uses range from the obvious, such as false eyelashes and wigs, to the more obscure: it's a common raw-material source for l-cysteine, an amino acid frequently used in baked goods such as pizza dough and bagels.

China and India exported more than $154 million worth of human hair last year, according to United Nations trade statistics. They are Blacker's main suppliers.

"It's not processed or dyed like a lot of hair we have here," said Blacker, whose own hair is silvery and neatly cropped.

The product, marketed as SmartGrow, is effective in keeping out weeds, and has even shown signs of increasing yield in crops like tomatoes, according to University of Florida scientists.

"It's really exciting. The first trial was just outstanding," said Aaron Palmateer, an associate professor of plant pathology who has conducted tests on the SmartGrow product at UF's Tropical Research and Education Center in Homestead.

There is an admitted yuck factor to using hair in lieu of herbicide, but Palmateer points out that common agricultural methods can be similarly unappetizing.

"For people who say, 'Oh my God, this is hair' and think it's disgusting, they should know these farmers put manure on tomatoes like its going out of style," said Palmateer.

Luis Naranjo, owner of one of the largest wholesale nursery operations in South Miami-Dade, swears by the hirsute stuff.

"In the beginning, we were saying, 'Human hair? What is this?"' said Naranjo. He now expects 80 percent of his nearly 1 million plants, like ground orchids, at Octavio Taylor Nurseries will be cozily blanketed with the mats by this spring.

The hair mats saved him $45,000 in pesticides last year, and $200,000 in labor. "We can't raise our prices the way the market is today, so we need to keep expenses down," said Naranjo, who has been a grower for two decades.

The mats range in size from 25-foot sheets that can be custom-cut for row crops like tomatoes to golfball-sized cubes to tuck around the roots of potted ficus trees.

Wal-Mart began selling the mats for home gardeners last spring in about 60 stores in central Florida. Dollar General just signed on to sell the smaller-size sheets at 1,000 of its stores.

SmartGrow relies on two hair brokers — in China and India — to procure the hair, which is boiled in 120-degree water, dried, loaded onto 40-foot boats and shipped via waterway to a port city in China. Then it is transported to the small town of Zhaoyuan, home of the SmartGrow factory.

The mass of strands is loaded onto an old-style needle-punch machine, formerly used to make carpets.

A hopper blows air through the hair to loosen it, and the strands are then woven into a loose felt-like mat of mostly dark and shiny follicles, with the occasional gray strand peeping through.

SmartGrow began as the brainstorm of Phil McCrory, an Alabama hairstylist, nearly 20 years ago. McCrory was watching television coverage of the massive oil spill in Alaska caused by the Exxon Valdez in 1989, when he noticed oil-covered otters swimming to shore.

"I noticed how their fur soaked up the oil, and it just clicked," said McCrory, who used the clippings from his Huntsville salon — and his wife's pantyhose — to develop a prototype.

A few years later, Blacker was running a company in Alabama, World Response Group, that specialized in oil and chemical remediation products when a colleague walked into his office with a matted wad of McCrory's making.

Blacker bought the patent from McCrory — but found the oil industry wasn't interested. Then he started getting calls from growers wanting to buy his product in bulk.

"That blew my mind," said Blacker, who was surprised to learn that hair had a folk-remedy reputation for repelling deer and fertilizing plants.

"It was sort of an old wives' tale," said Blacker. He shut down the business, boned up on the science of hair, and decided to relocate to the Homestead area to be closer to the agricultural industry — and potential customers.

McCrory gave up hairstyling to sell what he used to sweep into the garbage. He also stands to make royalties if SmartGrow takes off.

The company's sales team has been met with a few raised eyebrows.

One grower in North Carolina, after hearing the sales pitch, "asked if he was on Candid Camera," said Mike Foley, executive vice president in charge of sales.

The hair mats recently received certification from the Organic Materials Review Institute allowing it to be used on farms complying with USDA-approved organic methods. Another group of UF scientists at the Gulf Coast Research and Education Center in Balm, Florida, are studying the hair mats' effect on bell peppers, blueberries and other crops.

Palmateer, the UF scientist, is now examining why the mats are increasing plant growth and crop yield.

"It's still one of the unknowns," said Palmateer, who said he's noticed a "significant" increase in the yield of tomato plants grown in containers.

The original use for the mats may be making a comeback, too.

The oil-capturing hair mats, marketed by Blacker's company as Ottimats, were used after an oil spill off the coast of California in November.

A video of activists using the hair mats to swipe the tarry mess off a San Francisco beach has been posted on YouTube.

"It seemed to work pretty well, and it's bio-neutral," said Lance Contreras, San Francisco's operations commander for the clean-up effort.

Which is good news for Blacker, who is considering broadening sales beyond the Southeast to the West Coast.

"Here we are in little ole Florida City," said Blacker. "And we're going to help the world go green."