Sep 28, 2012

Pop Star Claims Sex With Ghost

Artists and musicians are always seeking inspiration for their work, and in a recent radio interview with Ryan Seacrest, pop star Kesha talked about the inspiration for her new song "Supernatural." While many singers like Taylor Swift and Adele produce heartfelt songs about love and loss, Kesha's was a little different.

"There are so many weird topics on this record from having sexy time with a ghost to getting hypnotized and going into past lives. I just really wanted the theme of this record to be the magic of life," she told Seacrest.

Yes, "having sexy time" means what you think it means: Her song is about the time she had sex with a ghost. "I had a couple of experiences with the supernatural. I don't know his name! He was a ghost! I'm very open to it....I was in Africa rehabilitating baby lions. I went diving with great white sharks, and just went on this crazy spirit quest. I got hypnotized, and I just really wanted this record to be really positive, really raw, really vulnerable and about the magic of life."

While this may seem like a bizarre (or publicity-savvy) revelation, Kesha is not alone; in fact many people have reported similar sexual experiences with spirits... and psychologists may have an explanation.

Succubi, Incubi, and Psychology

This phenomenon is not new, and is the basis for medieval legends about male and female demons (incubus and succubus respectively), who sexually attack people at night in their sleep. In centuries past, a woman claiming to have had sexual relations with an unseen spirit would likely have been accused of witchcraft. Indeed, the notorious 1486 witch-hunting text "Malleus Maleficarum" contains a section titled, "Here follows the Way whereby Witches copulate with these Devils known as Incubi," in which the authors explain that sex with the unknown is inherently evil and a clear sign of congress with Satan.

In his book "The Terror that Comes in the Night," folklorist David J. Hufford estimates that about 15 percent of people experience being assaulted in their sleep by an unknown entity at some point in their lives.

These attacks -- sometimes scary, sometimes sexy, but always realistic to the person experiencing them -- are the result of normal brain misperceptions and illusions. Last year a British grandmother complained of being sexually assaulted by a ghost while in bed. She felt "a creepy pair of hands" groping her as she tried to sleep, though no one else was around.

Kesha did not elaborate on the circumstances behind her exciting encounter with the anonymous phantom paramour, but it's likely she experienced it in bed either while sleeping, or going into or out of sleep. Psychologists know that this is a time when people are vulnerable to common (and harmless) hallucinations -- including sexual experiences.

Read more at Discovery News

'Jesus Wife' Papyrus Deemed a Fake

The "Jesus Wife" papyrus, a fragment of Coptic script containing a suggestion that Jesus may have been married, is a "clumsy forgery," the Vatican said.

"At any rate, a fake," Giovanni Maria Vian, the editor of the Vatican's newspaper L'Osservatore Romano, wrote in an editorial that accompanied an article by leading Coptic scholar Alberto Camplani.

The brownish-yellow, tattered fragment, about one and a half inches by three inches, was unveiled last week by Harvard Professor Karen L. King at an international congress of Coptic Studies, held every four years and hosted this year by the Vatican's Institutum Patristicum Augustinianum in Rome.

 Featuring just eight lines of text on the front and six lines on the back, the fragment was dated from a fourth-century dialogue, written in Coptic, a language of ancient Egyptian Christians, between Jesus and his disciples.

The center of the fragment contained the bombshell phrase "Jesus said to them, my wife," suggesting that some early Christians believed Jesus had been married.

"The news was quickly reported," Camplani wrote, criticizing Harvard for handing the headline-grabbing announcement to the American press before the conference even started.

 According to the historian, who teaches history of Christianity at the University La Sapienza of Rome and helped organize the conference, the fact that there is no reference to Jesus being married in historic documents is "more significant than the literal interpretation of a few expressions from the new text."

The papyrus provenance also screams for caution, Camplani said.

"It was not discovered in a dig but came from the antique market. Such an object demands that numerous precautions are taken to establish its reliability and exclude the possibility of forgery," he wrote.

Camplani has joined a growing number of skeptical experts.

"Skepticism is exactly the right attitude," Francis Watson, a New Testament scholar at Durham University, UK, wrote in a paper posted online.

Watson dismissed the text as a forgery, arguing that the fragment is a patchwork of words and phrases copied from printed editions of the Gospel of Thomas.

Read more at Discovery News

Ancient Burial Shroud Made of Surprising Material

Ancient scraps of fabric found in a grave in Denmark are not made of cultivated flax as once believed, but instead are woven from imported wild nettles, suggesting the grave's inhabitant may have traveled far for burial.

This discovery, announced today (Sept. 28) in the journal Scientific Reports, casts a new light on the textile trade in Bronze Age Europe, said study researcher Ulla Mannering, an archaeologist at the University of Copenhagen.

"Since the Stone Age, they had very well-developed agriculture and technology for producing linen textiles," Mannering told LiveScience. "So it's really unusual that a society which has established agriculture would also take in material from things that are not of the normal standardized agricultural production" -- in other words, wild plants.

A luxurious shroud

The soft and shiny fabric dates back to between 940 B.C. and 750 B.C., making it about 2,800 years old. It was discovered in Voldtofte, Denmark, at a rich Bronze Age burial ground called Lusehøj. The Bronze Age ran from about 3200 B.C. to 600 B.C. in Europe.

The fabric was wrapped around a bundle of cremated remains in a bronze urn. It was a luxurious piece of material, Mannering said.

"The fibers we get from the European nettle are very, very fine and soft and shiny, and we often say this is a sort of prehistoric silk textile," Mannering said. (Silk, made from insect cocoons, is known for its shimmery texture.)

Previous analysis pegged the Danish fabric as woven from flax, a plant widely cultivated in the region. But along with nanophysicist Bodil Holst of the University of Bergen in Norway, Mannering and her colleagues used advanced methods to reanalyze the scraps of cloth. By studying the fiber orientation as well as the presence of certain crystals found in plants, the researchers were able to learn that the fabric is not flax at all, but nettle, a group of plants known for the needlelike stingers that line their stems and leaves.

Nor is the nettle local, Mannering said. Different soil regions contain different variations of elements. The variation of one of these elements, strontium, found in the fabric, was not local to Denmark, suggesting the plants the textile was made from grew elsewhere.

There are a few regions that match the strontium profile, the researchers found, but the most likely candidate is southwest Austria. The bronze burial urn holding the remains is from Austria, Mannering said, and it makes sense that the fabric might be too.

A well-traveled man?

Despite these imported grave goods, the remains appear to be those of a Danish man, Mannering said. The personal objects in the grave, such as two razors, suggest he was a Scandinavian, albeit perhaps a well-traveled one, she said.

"Maybe he died in Austria and was wrapped in this Austrian urn and Austrian textile and was brought back to Denmark in this condition and then put in a big burial mound," Mannering said. "The personal objects that were placed inside the urn together with this textile and the bones indicate that he is a male of Scandinavian origin, but it doesn't mean that he couldn't have died abroad."

Read more at Discovery News

Giant Crocs Ruled Ancient Seas

An over 22-foot-long crocodile that ripped prey to death and another huge croc that sucked prey to its doom were at the top of the European marine food chain 150 million years ago, a new study finds.

The enormous prehistoric crocodiles, Plesiosuchus and Dakosaurus, were such ravenous carnivores that their methods have been compared to today's killer whales and a famous, iconic, meat-loving dinosaur.

"The skulls of these two sea croc species have some similarities to T. rex," lead author Mark Young of the University of Edinburgh told Discovery News. "The largest known skull of Plesiosuchus manselii was approximately four feet, three inches long, putting it in the size range of adult T. rex skulls."

For the study, published in PLoS ONE, Young and his colleagues analyzed fossils for the two crocodiles, which were unearthed in sites from England to Germany. In their U.K. home, the crocs once dwelled in the shallow seas that covered England. At the same time, Archaeopteryx was flying over Europe and giant dinosaurs, such as Diplodocus and Allosaurus, were stomping around North America.

The researchers determined that Plesiosuchus was the largest known species of metriorhynchid, meaning sea crocodile.

"It was bigger than living salt water crocodiles and great white sharks," Young said.

Its teeth functioned like those of today's killer whales, based on shape and wear. This ripper crocodile probably bit into both large and small prey, which it would grab, kill and gulp.

Perhaps even more unusual was the sucker croc, Dakosaurus. The skull and jaw characteristics of this nearly 15-foot-long ancient crocodile suggest that it was a suction feeder, making it the first known suction-feeding crocodilian.

This way of eating "involves being able to rapidly open the mouth wide, and generating negative pressure," Young said. "This sucks a prey item into the mouth."

"We think that Plesiosuchus specialized in eating other marine reptiles, and Dakosaurus was a generalist," co-author Lorna Steel of the Natural History Museum in London said, "probably eating fish and whatever else it could get hold of, perhaps including the small metriorhynchid Geosaurus." The latter looked like a barracuda.

It's suspected that modern killer whales can also suck in victims. Young explained that juvenile killer whales in captivity are known to generate negative pressures with their mouths.

Both prehistoric crocodiles, therefore, fed very similar to modern killer whales. These animals are not related, since killer whales are mammals. The researchers instead believe that the similarities exemplify what's known as convergent evolution.

"Convergence is the evolution of a similar body plan, feeding mechanism (or other characteristic or behavior) in two different and not closely related groups, in this case crocodiles and mammals," Young said.

Read more at Discovery News

Lightning Still Largely a Mystery

Some 44,000 thunderstorms rage worldwide each day, delivering as many as 100 lightning bolts to the ground every second. These dramatic, deafening flashes of electricity recharge the global battery by keeping the ground flush with negative electric charge and maintaining the ionosphere's positive charge. Lightning turns the Earth into an electric circuit, and it may have even delivered the spark that got life started in the primordial soup.

But for all we know, lightning might as well come from Zeus. Counting Ben Franklin's kite-and-key experiment as the starting point, 250 years of scientific investigation have yet to get to grips with how lightning works.

Atmospheric scientists have a basic sketch of the process. Positive electric charges build up at the tops of thunderclouds and negative charges build up at the bottoms (except for perplexing patches of positive charges often detected in the center-bottom). Electrical attraction between these opposite charges, and between the negative charges at the bottom of the cloud and positive charges that accumulate on the ground below, eventually grow strong enough to overcome the air's resistance to electrical flow.

Like a herd of elephants wading across a river, negative charges venture down from the bottom of the cloud into the sky below and move haltingly toward the ground, forming an invisible, conductive path called a "step leader." The charges' path eventually connects to similar "streamers" of positive charges surging up from the ground, completing an electrical circuit and enabling negative charges to pour from the cloud to the ground along the circuit they have formed. This sudden, enormous electric discharge is the flash of lightning.

But as for how all that happens — well, it just doesn't make much physical sense. There are three big questions needing answers, said Joe Dwyer, a leading lightning physicist based at the Florida Institute of Technology. "First, how do you actually charge up a thundercloud?" Dwyer said. A mix of water and ice is needed to provide atoms that can acquire charge, and updrafts are required to move the charged particles around. The rest of the details are hazy.

One theory holds that high-energy cosmic rays from space shoot down through the cloud, stripping off electrons from atoms as they go and dragging these negatively charged particles toward the cloud base, creating a charge imbalance. Dwyer said that although this process may play a role, it doesn't seem sufficient to explain the huge imbalance that scientists observe.

The consensus among scientists, he told Life's Little Mysteries, is that charge separation is mainly achieved in a process called "non-inductive charging mechanism."

"You have a mixed phase of ice and water up above 5 kilometers (3 miles) or so, and somehow those interact with each other and you have some kind of precipitation, and you have updrafts blowing up," he said. "Somehow the ice and water interact and manage to separate into oppositely charged particles. The lighter particles acquire positive charge and get blown to the top, and the heavier ones are negative and fall down."

That aforementioned positive patch near the bottom of the cloud remains a head-scratcher.

The second point of confusion is called the "lightning initiation problem." Measurements of the electric fields inside thunderclouds have consistently yielded peak values that are an order of magnitude weaker than is needed to break down the insulating properties of air. Man-made spark plugs require a much bigger electric field, or voltage difference between one electrode and the other in order for a current to tear across the gap. So the question is, "How do you get a spark going inside a thunderstorm? The electric fields never seem to be big enough inside the storm to generate a spark. So how does that spark get going? This is a very active area of research," Dwyer said.

Read more at Discovery News

Sep 27, 2012

Simulations Uncover 'Flashy' Secrets of Merging Black Holes

According to Einstein, whenever massive objects interact, they produce gravitational waves -- distortions in the very fabric of space and time -- that ripple outward across the universe at the speed of light. While astronomers have found indirect evidence of these disturbances, the waves have so far eluded direct detection. Ground-based observatories designed to find them are on the verge of achieving greater sensitivities, and many scientists think that this discovery is just a few years away.

Catching gravitational waves from some of the strongest sources -- colliding black holes with millions of times the sun's mass -- will take a little longer. These waves undulate so slowly that they won't be detectable by ground-based facilities. Instead, scientists will need much larger space-based instruments, such as the proposed Laser Interferometer Space Antenna, which was endorsed as a high-priority future project by the astronomical community.

A team that includes astrophysicists at NASA's Goddard Space Flight Center in Greenbelt, Md., is looking forward to that day by using computational models to explore the mergers of supersized black holes. Their most recent work investigates what kind of "flash" might be seen by telescopes when astronomers ultimately find gravitational signals from such an event.

Studying gravitational waves will give astrophysicists an unprecedented opportunity to witness the universe's most extreme phenomena, leading to new insights into the fundamental laws of physics, the death of stars, the birth of black holes and, perhaps, the earliest moments of the universe.

A black hole is an object so massive that nothing, not even light, can escape its gravitational grip. Most big galaxies, including our own Milky Way, contain a central black hole weighing millions of times the sun's mass, and when two galaxies collide, their monster black holes settle into a close binary system.

"The black holes orbit each other and lose orbital energy by emitting strong gravitational waves, and this causes their orbits to shrink. The black holes spiral toward each other and eventually merge," said Goddard astrophysicist John Baker.

Close to these titanic, rapidly moving masses, space and time become repeatedly flexed and warped. Just as a disturbance forms ripples on the surface of a pond, drives seismic waves through Earth, or puts the jiggle in a bowl of Jell-O, the cyclic flexing of space-time near binary black holes produces waves of distortion that race across the universe.

While gravitational waves promise to tell astronomers many things about the bodies that created them, they cannot provide one crucial piece of information -- the precise position of the source. So to really understand a merger event, researchers need an accompanying electromagnetic signal -- a flash of light, ranging from radio waves to X-rays -- that will allow telescopes to pinpoint the merger's host galaxy.

Understanding the electromagnetic counterparts that may accompany a merger involves the daunting task of tracking the complex interactions between the black holes, which can be moving at more than half the speed of light in the last few orbits, and the disks of hot, magnetized gas that surround them. Since 2010, numerous studies using simplifying assumptions have found that mergers could produce a burst of light, but no one knew how commonly this occurred or whether the emission would be strong enough to be detectable from Earth.

To explore the problem in greater detail, a team led by Bruno Giacomazzo at the University of Colorado, Boulder, and including Baker developed computer simulations that for the first time show what happens in the magnetized gas (also called a plasma) in the last stages of a black hole merger. Their study was published in the June 10 edition of The Astrophysical Journal Letters.

The simulations follow the complex electrical and magnetic interactions in the ionized gas -- known as magnetohydrodynamics -- within the extreme gravitational environment determined by the equations of Einstein's general relativity, a task requiring the use of advanced numerical codes and fast supercomputers.

Both of the simulations reported in the study were run on the Pleiades supercomputer at NASA's Ames Research Center in Moffett Field, Calif. They follow the black holes over their last three orbits and subsequent merger using models both with and without a magnetic field in the gas disk.

Additional simulations were run on the Ranger and Discover supercomputers, respectively located at the University of Texas, Austin, and the NASA Center for Climate Simulations at Goddard, in order to investigate the effects of different initial conditions, fewer orbits and other variations.

"What's striking in the magnetic simulation is that the disk's initial magnetic field is rapidly intensified by about 100 times, and the merged black hole is surrounded by a hotter, denser, thinner accretion disk than in the unmagnetized case," Giacomazzo explained.

In the turbulent environment near the merging black holes, the magnetic field intensifies as it becomes twisted and compressed. The team suggests that running the simulation for additional orbits would result in even greater amplification.

The most interesting outcome of the magnetic simulation is the development of a funnel-like structure -- a cleared-out zone that extends up out of the accretion disk near the merged black hole. "This is exactly the type of structure needed to drive the particle jets we see from the centers of black-hole-powered active galaxies," Giacomazzo said.

Read more at Science Daily

Woman Survives Rare Internal Decapitation

Rachel Bailey did not lose her head over temporarily losing her head. The 23-year-old Phoenix resident is making a miraculous recovery after a car accident fully separated her skull from her spine, a rarely seen and even more rarely survived injury called an internal decapitation.

"I just thought, 'I'm not going to let this beat me, I'm not going to let this define me,'" Bailey told Arizona TV station 3TV of the injury that put her in an intensive care unit for a month after the car crash in September 2011.

After six surgeries and extensive physical therapy, Bailey recovered her ability to walk and talk, and on Monday (Sept. 24) she had dinner with the Phoenix firefighters whose speedy work saved her from paralysis, according to 3TV.

Internal decapitation, or atlanto-occipital dislocation, occurs when head trauma separates the skull from the spinal column while leaving the exterior of the neck intact. According to a 2006 study in the Canadian Journal of Emergency Medicine, the sensation of instability that results when part or all of the spinal column is severed in a still-conscious person "may cause patients to experience the sensation that their 'head is falling off.'"

Read more at Discovery News

Is This Mona Lisa's First Smile?

So, has the world found Mona Lisa's first smile?

A younger and happier version of Leonardo Da Vinci's masterpiece has been presented today in Geneva with the suggestion that the painting was executed by the Renaissance master approximately a decade earlier than the iconic picture that hangs in the Louvre.

Known as the Isleworth Mona Lisa, the artwork has been the focus of a 35 years of research, which has been summarized in a 320-page book published by The Mona Lisa Foundation, a non-profit organization based in Zurich, Switzerland, and a video.

Listing historical and archival records, scientific and experimental data, the book aims to support the theory that the painting is the original portrait of Lisa Gherardini del Giocondo, while the Louvre masterpiece is a later version, completed in Rome around 1516 at the encouragement of Lorenzo de' Medici's brother Giuliano.

"Historical evidence suggests that Leonardo da Vinci left unfinished an earlier portrait of Mona Lisa in which she is flanked by side columns," the Mona Lisa Foundation said in a statement.

Slightly larger in size than the Louvre portrait, the Isleworth painting indeed shows an unfinished background framed by two columns. It features a darker tonality while depicting a younger lady with a less enigmatic smile.

Although it has been hailed as a new finding, the Isleworth Mona Lisa is not unknown to art historians. Its authenticity has been the subject of debate ever since the canvas was discovered in 1913 by English art collector Hugh Blaker. He bought it from a noble family‭ who had owned it for 150 years ‬and took it to his studio in Isleworth, London –- hence the name.

In‭ ‬1915 his stepfather John R. Eyre, an art historian, published a book suggesting that Leonardo painted two versions of the Mona Lisa and claiming that at least the bust, the face and the hands of the Isleworth lady were a genuine work by Leonardo Da Vinci –- basically, a prequel to his famous portrait.

The story of the painting continues with the American collector Henry F. Pulitzer. He bought the artwork in 1962, then brought it to Switzerlawly and left it secured in a bank vault. It remained there for 40 years.

The artwork is now owned by an international consortium that remains anonymous. The consortium acquired the canvas from the estate of Pulitzer’s late partner in 2008 and entrusted it to The Mona Lisa Foundation for deeper research.

According to the foundation's experts, four  historical accounts strongly point to existence of two Mona Lisa portaits.

In his work‭ "‬Lives of the Artists," 16th century painter and art historian Giorgio Vasari(1511–1574) named Lisa Gherardini, the wife of the wealthy Florentine silk merchant Francesco del Giocondo as the subject of the portrait. He dated the painting shortly after Leonardo’s return to Florence in 1500, and stated that it was left unfinished after four years.

Vasari's version is confirmed by an acquaintance of Leonardo da Vinci, Florentine city official Agostino Vespucci, a relative of the explorer, navigator and cartographer Amerigo Vespucci.

Perhaps the earliest witness of the masterpiece, Agostino Vespucci wrote in October 1503 that Leonardo was working on three paintings at the time, including a portrait of Lisa del Giocondo. Vespucci's annotations were found in 2005 at the Heidelberg University's library.

Another account can be found in the travel journal of Antonio De Beatis, the secretary of the cardinal Louis d'Aragona. Written between 1517and 1518, the diary reported that Leonardo had finished the Mona Lisa by 1517, and that it was completed for Giuliano de’ Medici.

To add to the contradiction, the account of the Renaissance historian Gian Paolo Lomazzo (1538 – 1592) referred in his‭ ‬1584 Treatise on Painting, to "a Gioconda and a Mona Lisa."

"The accounts are totally different from each other, and were written decades apart. Taken together, they point to two distinct and different portraits, one being of the young Mona Lisa, and the second to a 'Florentine woman,' or 'La Gioconda,'" the Mona Lisa Foundation said.

La Gioconda is the Italian alternative name for the Mona Lisa hanging in the Louvre.

"The historical evidence suggests that the earlier version of Mona Lisa, the portrait of Lisa del Giocondo, was probably delivered unfinished into the hands of her husband Francesco before Leonardo departed Florence for Milan in 1506," the Mona Lisa Foundation wrote.

Further historical evidence would come from a drawing by Raphael of the Mona Lisa.‭ ‬Now in the Louvre, the drawing was probably done from memory from Leonardo's original after Raphael visited the master's studio in 1504.

Featuring two columns, the sketch mirrors that of the Isleworth painting.

"The artwork indeed reminds Raffaello's drawing and raises many questions," Alessandro Vezzosi, the director of the‭ ‬Museo Ideale in the Tuscan town of Vinci, where Leonardo was born in 1452, said.

Along with leading Da Vinci expert Carlo Pedretti of the Armand Hammer Center for Leonardo Studies at the University of California, Vezzosi is carrying an independent research on the puzzling Isleworth painting.

He suggested that most likely several hands worked on the canvas.

"Just compare the face with its quality and intensity with the cluster of trees in the backdrop. The trees reveal a different technique and problems of perspective. Most likely, they were painted by someone else," Vezzosi said.

In the past twelve years, the painting underwent any possible test, from gamma rays and infrared reflectography to forensic age regression to determine what the Louvre Mona Lisa would have looked like 11 to 12 years earlier.

But it was mathematics that helped the foundation's experts to discover what they called "Leonardo's hidden technique."

Simple horizontal lines drawn across both the Louvre and the Isleworth paintings -- previously brought to the same ratio -- show exact proportional similarities despite the fact that, in reality, the figures within them were not painted to the same size.

"The eyes, the nose, the distance between the mouth and the chin, are exactly in the same location. Only the same artist could have known how to do that without the benefit of modern technological aids," art historian Stanley Feldman, principal author of the 320 page book, said.

As expected, the claim is raising a controversy in the art world.

Vezzosi called the suggestion that Da Vinci portrayed Lisa del Giocondo at two different moments of her life "a fascinating possibility," but according to Oxford professor Martin Kemp "there is no basis for thinking that there was an earlier portrait."

Read more at Discovery News

Is Antimatter a Viable Starship Fuel?

Hope springs eternal for die-hard Star Trek fans that scientists will one day build an actual, working antimatter propulsion engine similar to the one that powers the fictional starship Enterprise.

A paper published earlier this year by a pair of enterprising (get it?) physicists should fan the flames of that fantasy even further.

Ronan Keane (Western Reserve Academy) and Wei-Ming Zhang (Kent State University) report that the latest results from their computer simulations indicate that at least one key component of realizing a working antimatter propulsion engine -- highly efficient magnetic nozzles -- should be far more efficient than previously thought. And such nozzles are feasible using today's technologies.

Before everyone chimes in with a resounding "Squee!", let's back up a moment.

First, its true: matter/antimatter propulsion is not just the stuff of science fiction. As he did with many technical aspects of the series, for the Enterprise propulsion system, Star Trek creator Gene Roddenberry drew on science fact.

Antimatter is the mirror image of ordinary matter. So antiparticles are identical in mass to their regular counterparts, but the electrical charges of antiparticles are reversed. An anti-electron would have a positive instead of a negative charge, while an antiproton would have a negative instead of a positive charge.

When antimatter meets matter, the result is an explosion. Both particles are annihilated in the process, and their combined masses are converted into pure energy -- electromagnetic radiation that spreads outward at the speed of light.

Remember in Star Trek III: The Search for Spock: when Kirk sabotages the Enterprise after surrendering his ship to the Klingons? He programs the computer to mix matter and antimatter indiscriminately. Ka-boom! The ship is destroyed.

Despite that whole annihilation thing, as recently as October 2000, NASA scientists were developing early designs for an antimatter engine for future missions to Mars.

Antimatter is an ideal rocket fuel because all of the mass in matter/antimatter collisions is converted into energy. Matter/antimatter reactions produce 10 million times the energy produced by conventional chemical reactions such as the hydrogen and oxygen combustion used to fuel the space shuttle.

We're talking reactions that are 1,000 times more powerful than the nuclear fission produced at a nuclear power plant, or by the atomic bombs dropped on Hiroshima and Nagasaki. And they are 300 times more powerful than the energy released by nuclear fusion

Alas, the only way to produce antimatter is in large accelerators at places like CERN. Even the most powerful atom smashers only produce minute amounts of antiprotons each year -- as little as a trillionth of a gram, which would barely light a 100-watt bulb for three seconds.

It would take tons of antimatter to fuel a trip to distant stars. It would take CERN roughly 1,000 years to produce one microgram of antimatter.

Should an ample supply of antimatter be found, a secure means of storage must then be devised; the antimatter must be kept separate from matter until the spacecraft needs more power. Mixing can’t occur all willy-nilly, because then the two would annihilate each other uncontrollably, with no means of harnessing the energy.

But these are trivial engineering concerns, surely. The point is, Keane and Zhang think they've solved one part of the conundrum. Any rocket's maximum speed depends on the configuration of the rocket stages, how much of the total mass is devoted to fuel, and a little something called exhaust velocity that provides the all-important thrust.

Keane and Zhang focus on the latter in their paper, i.e., how fast all those particles resulting from (hypothetical) matter-antimatter annihilation are traveling as they whip out of the rocket engine. Their premise relies on charged pions resulting from proton-antiproton collisions. A nozzle that emits a strong magnetic field could channel the emitted charged particles into a focused stream of charged pions, accelerating them to produce stronger thrust.

All this is old hat. And here's the sticking point to that plan. The exhaust velocity of those pions depends partly on how fast they're moving as they emerge from the annihilation event, and partly on the efficiency of the magnetic nozzle design.

Past calculations have shown that while the pions' initial speed would be over 90 percent the speed of light, the magnetic nozzle would only be 36 percent efficient, so the largest escape velocity that could be achieved would be a disappointing one-third of light speed.

There isn't much human beings can do to jack up the pions' initial speed, so clearly the way to tackle this problem is to focus on the design of the magnetic nozzle. That's exactly what Keane and Zhang did, relying on CERN software designed to simulate the complex interactions between particles, matters and fields so physicists can better understand the behavior of all those particles produced in collisions at the Large Hadron Collider.

Read more at Discovery News

Sep 26, 2012

Ancient Buddha Carved From Meteorite

German scientists have discovered an ancient Buddhist statue with extraterrestrial origin.

Depicting Vaisravana, the Buddhist god of wealth or war, the sculpture was carved from an ataxite, a rare class of iron meteorite with high contents of nickel.

"The statue was chiseled from an iron meteorite, from a fragment of the Chinga meteorite which crashed into the border areas between Mongolia and Siberia about 15.000 years ago," said Elmar Buchner of the University of Stuttgart.

In a paper published in Metoritics and Planetary Science, Buchner and colleagues reported their geochemical analysis and the story of the "Buddha from Space," which almost reads like an Indiana Jones movie.

Known as the Iron Man, the 9.5-inch-high statue was discovered in 1938 by an expedition backed by SS chief Heinrich Himmler and led by zoologist Ernst Schäfer. The expedition roamed Tibet to search for the roots of Aryanism.

It is unknown how the sculpture was unearthed, but it is believed that a large swastika carved into the center of the figure may have encouraged the team to take it back to Germany.

Once it arrived in Germany, the Iron Man became part of a private collection and it wasn't until 2009 that cientists could study it, following an auction.

Weighting about 23 pounds, the statue wasn't exactly carved from the most appropriate material. Buchner and colleagues noted that the artist who created it from the extremely hard meteorite may have known that the material was special.

"The fall of meteorites has been interpreted as divine messages by multitudinous cultures since prehistoric times," they wrote.

According to Buchner, the statue was likely carved about 1,000 years ago by the pre-Buddhist Bon culture of the 11th century. However, the exact origin and age of the statue remains unknown.

Read more at Discovery News

Spiny Mouse Skin Peels and Reseals

For the first time, biologists studied a mouse native to Africa that can escape predators by losing patches of skin that regrow quickly. Their research could one day lead to scar-free tissue regrowth for humans.

The African spiny mouse in the Acomys genus literally jumps out of its skin when grabbed, losing up to 60 percent of it. Turns out these deep lesions regenerate rapidly without scarring. Biologists led by postdoc fellow Ashley W. Seifert at the University of Florida caught two wild mice and tested them to find out what causes this phenomenon. Their paper will be published in Nature on Thursday.

"These guys had been known to lose their tail, but no one had ever reported on skin dislodging from their body," Seifert said.

When Seifert and his colleagues trapped two mice in central Kenya, an Acomys kempi and an Acomys percivali, just handling the mice in the field caused them to lose skin. Seifert compared it to the difference between grabbing a paper towel and a piece of tissue paper.

The biologists found that after only three days, five of the six skin wounds had completely "re-epithelialized." Perhaps even more impressive: The mice could regrow damaged hair, retaining the original color, within 30 days.

That feat is incredibly difficult for mammals to achieve according to Elly Tanaka, a professor specializing in animal models of regeneration at the Technical University of Dresden who also wrote a commentary for Nature's News and Views section. Usually that kind of rapid regrowth is only found in amphibians like salamanders.

In order to test just how well the mice could regenerate tissue, the biologists hole-punched the mice's ears. The holes closed up in a way reminiscent of how salamanders regenerate limbs, Seifert said.

"This study," the authors wrote, "suggests that mammals may retain a higher capacity for regeneration than was previously believed." Although, as Tanaka pointed out, the biologists don't address whether the mouse's regenerative abilities also alter its immune response, the fact that mammals can do this is exciting.

Read more at Discovery News

305-Million-Year-Old Roach Recreated in 3-D

New three dimensional images of 305-million-year-old insects, including a prehistoric roach relative, have just been unveiled.

The images, published in the journal PLoS ONE, suggest that roaches and their predecessors haven't changed all that much over the years. You can see all of the bodily details, including the little legs that must have skittled around back in the pre-dino day.

Both of the insects are members of a group called the Polyneoptera, which includes roaches, mantises, crickets, grasshoppers and earwigs. The juvenile bugs fossilized in rock, so it's a mini tech miracle that they could be imaged.

To accomplish that, Russell Garwood of the University of Manchester's School of Materials and his colleagues placed the fossils in a CT scanner. They then took over 3,000 X-rays from different angles, creating 2,000 slices showing the fossil in cross section. From these slices the researchers created 3D digital reconstructions of the fossils.

"The roach nymph is much like modern day cockroaches -- although it isn't a 'true' cockroach, as it may well predate the split between true cockroaches and their sister group, the mantises," Garwood said in a press release.

"Around this time a number of early 'amphibians' were insectivores -- they lived by eating a lot of insects," he added. "The spiny creature was a sitting duck, as it couldn't fly, so the spines probably made it less palatable. It is bizarre -- as far as we're aware, quite unlike any members of the Polyneoptera alive today."

Read more at Discovery News

Quasars as Mileposts for Universal Expansion

In the late 1950s, radio telescopes picked up some unusual radio wave emissions from mysterious distant objects. Today, we know them as "quasars" -- short for "quasi-stellar radio sources" -- regions around the black holes at the center of massive galaxies that give off a great deal of radio waves, as well as visible light.

Black holes provide the power source. As matter -- gas and dust, primarily -- wanders near a black hole, it doesn't cross the event horizon and fall into the hole directly. Instead, it forms an accretion disk, and the light is the result of the energy produced as the black hole gobbles up that gas and dust.

Quasars have long been a boon to astronomers: images of a double quasar helped confirm Einstein's prediction of gravitational lensing in 1979. Now physicists have developed a new technique that uses light from quasars as cosmic mileposts to map the structure and expansion history of the universe -- possibly shedding light on the nature of dark energy, the favored culprit for our accelerating universe.

Based on data from the Massive Compact Halo Objects (MACHO) project, the work appeared in Physical Review Letters this summer.

The key is the high redshift patterns in quasar light, a direct effect of the expansion of the universe, since such a shift is indicative of an object moving away from us through space. A redshift in quasar light was first proposed by an astronomer named John Bolton in the 1960s. His colleagues were skeptical of the redshift claim initially, but subsequent work on the optical spectra of such objects verified that there were, indeed, high redshifts in the emission lines.

The higher the redshift, the further away the object. So based on the redshift data, it's clear that quasars are very far away, and hence date back to the earlier days of the cosmos. Physicists suspect that quasars were more common in the early universe than they are today, and that most galaxies -- including our own Milky Way -- have had their active "quasar moments," even if they are pretty quiet today.

So, how does this new technique exploit quasars? Case Western physicist Glen Starkman, one of the study's authors, said that his collaborators found that variation patterns in the light from 14 quasars over several hundred days proved very consistent -- Starkman described it as a "dimmer switch" -- and from that they could infer the redshift of each quasar.

Once they knew the redshift, they could use that information to determine what size our universe must have been when that light was first emitted, compared to the size it is today. The next step is to increase the sample size, to make sure this consistent variation pattern isn't just a statistical fluke.

Ultimately, the object is to calculate the redshifts of millions of quasars. That amount of data would enable them to map out the history of the universe, from those early quasar-filled days to the present, in great detail.

Read more at Discovery News

Hubble Goes Deep (WAY Deep) into the Cosmos

My god, it's full of ... galaxies.

Thousands and thousands of galaxies -- about 5,500 galaxies, to be exact -- are packed into this incredible image, made from over two million seconds of total exposure time with the Hubble Space Telescope. That's the equivalent of 50 days' worth of actual telescope time, not to mention 2,000 new images added to the previous Ultra Deep Field image... and the results are simply stunning.

With the exception of a handful of foreground stars that lie within our own Milky Way galaxy, every other point of light in this image is an entire galaxy of stars in itself, and we're seeing them as they were all the way back through time and space up to 13.2 billion years ago.

In fact the most distant galaxy in this image, called UDFj-39546284, is barely visible as a dim red dot and is seen as it existed after it first formed, a mere 450 million years after the Big Bang when the Universe was only 5 percent of its current age.

"The XDF is the deepest image of the sky ever obtained and reveals the faintest and most distant galaxies ever seen," said Garth Illingworth of UC Santa Cruz, principal investigator of the Hubble Ultra Deep Field 2009 program. Like a snapshot of billions of years of galactic evolution in progress, "XDF allows us to explore further back in time than ever before."

What's even more amazing is that all of these galaxies lie in a tiny patch of sky, less than a tenth of the diameter of the full moon, located within the constellation Fornax. For an idea of how big that is, take a dime, hold it out at arm's length, and inside less than a tenth of its width -- about the size of FDR's ear -- 5,500 galaxies can be found far beyond our own. (Although seeing them requires some pretty fancy equipment; the dimmest ones above are one ten-billionth the brightness that the human eye can make out!)

Read more at Discovery News

Sep 25, 2012

Understanding How Salamanders Grow New Limbs Provides Insights Into Potential of Human Regenerative Medicine

Based on two new studies by researchers at the Salk Institute for Biological Studies, regeneration of a new limb or organ in a human will be much more difficult than the mad scientist and supervillain, Dr. Curt Connors, made it seem in the Amazing Spider-man comics and films.

As those who saw the recent "The Amazing Spiderman" movie will know, Dr. Connors injected himself with a serum made from lizard DNA to successfully regrow his missing lower right arm -- that is, before the formula transformed him into a reptilian humanoid.

But by studying a real lizard-like amphibian, which can regenerate missing limbs, the Salk researchers discovered that it isn't enough to activate genes that kick start the regenerative process. In fact, one of the first steps is to halt the activity of so-called jumping genes.

In research published August 23 in Development, Growth & Differentiation, and July 27 in Developmental Biology, the researchers show that in the Mexican axolotl, jumping genes have to be shackled or they might move around in the genomes of cells in the tissue destined to become a new limb, and disrupt the process of regeneration.

They found that two proteins, piwi-like 1 (PL1) and piwi-like 2 (PL2), perform the job of quieting down jumping genes in this immature tadpole-like form of a salamander, known as an axolotl -- a creature whose name means water monster and who can regenerate everything from parts of its brain to eyes, spinal cord, and tail.

"What our work suggests is that jumping genes would be an issue in any situation where you wanted to turn on regeneration," says the studies' senior author, Tony Hunter, a professor in the Molecular and Cell Biology Laboratory and director of the Salk Institute Cancer Center.

"As complex as it already seems, it might seem a hopeless task to try to regenerate a limb or body part in humans, especially since we don't know if humans even have all the genes necessary for regeneration," says Hunter. "For this reason, it is important to understand how regeneration works at a molecular level in a vertebrate that can regenerate as a first step. What we learn may eventually lead to new methods for treating human conditions, such as wound healing and regeneration of simple tissues."

The research team, which included investigators from other universities around the country, sought to characterize the transcriptional fingerprint emerging from the early phase of axolotl regeneration. They specifically looked at the blastema, a structure that forms at a limb's stump.

There the scientists found transcriptional activation of some genes, usually found only in germlime cells, which indicated cellular reprogramming of differentiated cells into a germline state.

In the Development, Growth & Differentiation study, the research team, led by Wei Zhu, then a postdoctoral researcher in Hunter's laboratory, focused on one of these genes, the long interspersed nucleotide element-1 (LINE-1) retrotransposon.

LINE-1 elements are jumping genes that arose early in vertebrate evolution. They are pieces of DNA that copy themselves in two stages -- first from DNA to RNA by transcription, and then from RNA to DNA by reverse transcription. These DNA copies can then insert themselves into the cell's genome at new positions.

A few years ago, Fred Gage, professor in the Laboratory of Genetics at the Salk Institute, discovered that LINE-1 elements move around during neuronal development, and may program the identities of individual neurons.

"Most of these copies appear to be 'junk' DNA, because they are defective and can never jump again," says Hunter. But all mammals, including humans, still have active LINE-1 genes, and the salamander, whose genome is 10 times larger than a human's, contains many more.

Active LINE-1 retrotransposons can keep jumping, and that was true in the developing blastema where LINE-1 jumping was dramatically switched on. But in the researchers' companion study, in Developmental Biology, they found that PL1 and PL2 switch off transcription of repeat elements, such as LINE-1. "The idea is that in the development of germ cells, you definitely don't want these things hopping around," says Hunter. "The mobilization of these jumping genes can introduce harmful genomic rearrangements or even abort the regeneration process."

Read more at Science Daily

Einstein’s Brain Goes Digital With iPad App

For a man who never actually donated his brain to science, Albert Einstein’s grey matter sure does get around a lot. Obsessed with the late, great’s genius, as everyone of his day was, Princeton Hospital pathologist Thomas Harvey removed Einstein’s organ during an autopsy in 1955 without permission, and proceeded to slice it up into more than 200 cubes and slivers, preserve these in formaldehyde, then take them home. He lost his job after refusing to give the specimens up, despite getting permission from Einstein’s son retrospectively.

If it were not for the initiative, however creepy, that Harvey demonstrated while standing over the physicist’s rapidly decomposing body nearly six decades ago, we would not have the prize specimen we have today — an iPad app that offers the most detailed public access view of Einstein’s brain to date.

For $9.99, anyone can download the app and take advantage of digitised images of nearly 350 brain slices taken from the collection bequeathed to the National Museum of Health and Medicine in Silver Spring, Maryland by the Harvey family estate in 2010. The National Museum of Health and Medicine in Chicago digitized the slides for the app.

The app experience is touted as being like peering at this piece of history through a real microscope — the cellular structure and tissue definitions are visible, since Harvey stained each sample. Though it’s a great tool for students and researchers, there are a few issues with the finished product — namely, we’re not always certain what bit of the brain we’re actually looking at, despite Harvey taking a series of photos of the organ from different angles.

“They didn’t have MRI,” said Jacopo Annese of the University of California’s Brain Observatory, San Diego, who has digitised 2,400 slides from the brain of amnesiac Henry Molaison. “We don’t have a three-dimensional model of the brain of Einstein, so we don’t know where the samples were taken from.”

The app does organise the slides into general sections — brain stem, for instance — but cannot get more anatomically accurate than that.

Annese, whose work on Molaison’s brain will be accessible online from December 2012, predicts that there will be another Einstein, and when that individual dies, we’ll be prepared (we’re hanging on for that 3D-mapped interactive specimen).

Nevertheless, the app has finally preserved Einstein’s brain for future generations, so even as the samples begin to deteriorate we will always have this safe fail. It’s hoped that by making Einstein’s brain open source (well, pretty cheaply available to anyone with access to an iPad), studies will be more rapidly advanced.

In the 57 years since the great physicist died, we have managed to gather a few things from the samples. Harvey sent out slides to various researchers in his day, with results of varying degrees of success (there’s a great rundown here, taken from Brian Burrell’s Postcards from the Brain Museum), but probably the most well-noted investigation was Harvey’s own collaboration. The results, published in the Lancet in 1999, showed that the parietal lobe — associated with our processing of mathematics, language, and spatial understanding of things like maps — was 15 percent wider then normal. From analysing Harvey’s photos of the brain, it also became clear that parts of the brain were missing, including part of the Sylvian fissure and parts located in the frontal lobe.

According to Sandra Witelson, who worked on the paper, “This unusual brain anatomy may explain why Einstein thought the way he did… Einstein’s own description of his scientific thinking was that words did not seem to play a role. Instead he saw more or less clear images of a visual kind.” It was suggested that, because of how the brain developed and grew in this novel way, neurons may have been able to communicate better, or at least, in a different way.

Using the app, neuroscientist Phillip Epstein, a consultant to the National Museum of Health and Medicine, suggests researchers could look for areas where neurons are more densely connected than in “normal” brains.

So, as we battle away, attempting to prove that it’s not our fault we can’t get our heads round quantum physics in one afternoon — Einstein’s brain was just better — one question remains. Just how would the man himself, who requested that his remains only be cremated, feel about his organ being put on show for the world to scrutinise.

“I’d like to think Einstein would have been excited,” said Steve Landers, who consulted on the app, the proceeds of which are going to the National Museum of Health and Medicine and its Chicago branch, due to open in 2015.

“There’s been a lot of debate over what Einstein’s intentions were,” museum representative Jim Paglia said. “We know he didn’t want a circus made of his remains. But he understood the value to research and science to study his brain, and we think we’ve addressed that in a respectful manner.”

Read more at Wired Science

How Humans Lost Our Chance at a Third Eye

Lizards have a little dot at the top of their heads that is called a "parietal eye." This eye is not as complex or as useful as the two in the front of their heads, but it does react to light. Are they eventually going to have a third eye? No. It's just a vestigial trait.

In fact, it looks like most animals — including humans — had a chance at a third eye, and we blew it.

The tuatara is an endangered species, and lives on only a few islands in New Zealand, each of which is carefully maintained as a native animal preserve. It looks like a lizard, but isn't one. It's leftover from a time 200 million years ago, when tetrapods were turning into turtles, lizards, crocodiles, and dinosaurs. It hasn't changed since then, and so represents a look at what animals of that particular time period were like.

And it has a spot on the top of its head, which the closest thing anybody has to a third eye.

An extra eye presents a lot of evolutionary benefits. Being able to look up, or just behind you, for predators seems like an advantage to nearly any species. Although many lizards also have this spot, it has been lost in turtles, crocodiles, and birds. By examining the physiology and development of these species, from humans all the way back to the well-developed parietal eye of the tuatara, scientists are figuring out how later species lost a third eye, and what we might have gained in its stead.

How Humans Lost Our Chance at a Third Eye Perhaps the most notable feature of the third eye is that it's not symmetrical. Drop a line down the center of a body, even a developing body, and it's almost certain that the left and the right side will match. That's how regular eyes develop. They start off as dents in the developing roundness of the head. As the dents grow inwards, the finer structures of the eye develop. The parietal eye doesn't dip inwards. Instead, the outside of the whole structure is lined and becomes a kind of a bump, and inside two symmetrical parts of the brain structure develop. The left side of the brain becomes the parietal eye. The right side becomes the pineal sac. In reptiles, the parietal eye takes in light, and the pineal sac puts out melatonin, a hormone that regulates sleep cycles.

Read more at Discovery News

Black Hole Behemoth Shreds Baby Star System

The mantra among real estate brokers is "location, location, location..." This holds true for neighborhoods in our galaxy too.

One neighborhood to avoid is in the vicinity of the supermassive black hole -- inside a very strong radio source known as Sagittarius A* -- at the hub of the Milky Way.

A new analysis of recent observations finds evidence for a protoplanetary disk around a red dwarf star plunging in the direction of the black hole. Ruth Murray-Clay and Avi Loeb of the Harvard-Smithsonian Center for Astrophysics did the theoretical work. Stefan Gillessen of the Max-Planck-Institute for Extraterrestrial Physics made the observations using the European Southern Observatory's Very Large Telescope.

The red dwarf star will make its closest approach in the summer of 2013, hurtling only 270 billion miles from black hole. (Or roughly 54 solar system diameters, as measured from the furthest edge of the Kuiper belt.) It won't get sucked into the black hole, but it will be flung back along its elliptical orbit out to a distance of a little more than 1/10 light-years.

But the damage is already happening. The protoplanetary disk is disintegrating under the black hole's tidal pull -- stretching the disk like taffy. Add to that a withering blast of ultraviolet radiation from the black hole that is heating and driving off material in the disk.

Astronomers haven't seen the dim red star at the center of the disk, but infer its presence from a telltale 100 billion-mile diameter cloud of glowing gas created by the disintegration of the disk.

Superficially, the infalling star would resemble a comet with a teardrop shaped head of plasma and long trailing tail (shown in the picture at top of page).

Similar "distressed" protoplanetary disks can be found in the heart of the Orion nebula, where they are being blow-torched by a tsunami of radiation from the hottest central stars.

How did the doomed star end up on such a Kamikaze path? The farthest point of its orbit take its back to its nesting ground, a 3 million-year-old ring of young stars orbiting the black hole. The hapless star's orbit is in the plane of this ring.

The star was likely formed in the stellar ring and later thrown into its highly eccentric orbit though a close encounter with one or more stars in the ring. The stars exchanged momentum and the red dwarf was tossed onto a new, deadly trajectory.

If this event happens once every few hundred thousand years, it would agree with estimates for how much mass a quiescent black hole may gobble up over time. It might also show us a mechanism for explaining how active black holes that spew out deathly beams of plasma are fueled by a cascade of comets, asteroids and dust.

In the early 1990s, NASA's Hubble Space Telescope discovered a ring of blue stars encircling the black hole ring in the center of the neighboring Andromeda galaxy. There is also an outer elliptical ring of older stars. Therefore, black hole stellar rings appear to be common throughout the universe.

Most intriguing is the idea that planets can form in the stellar ring around a supermassive black hole. Could the planets be stable long enough for intelligent life to evolve in such neighborhoods? This is very hard to predict because we don't know how long the stellar ring will remain intact. What's more, dynamics within the densely pack ring might tear apart planetary systems.

Read more at Discovery News

Sep 24, 2012

Hubble Catches Glowing Gas and Dark Dust in a Side-On Spiral

The NASA/ESA Hubble Space Telescope has produced a sharp image of NGC 4634, a spiral galaxy seen exactly side-on. Its disk is slightly warped by ongoing interactions with a nearby galaxy, and it is crisscrossed by clearly defined dust lanes and bright nebulae.

NGC 4634, which lies around 70 million light-years from Earth in the constellation of Coma Berenices, is one of a pair of interacting galaxies. Its neighbor, NGC 4633, lies just outside the upper right corner of the frame, and is visible in wide-field views of the galaxy. While it may be out of sight, it is not out of mind: its subtle effects on NGC 4634 are easy to see to a well-trained eye.

Gravitational interactions pull the neat spiral forms of galaxies out of shape as they get closer to each other, and the disruption to gas clouds triggers vigorous episodes of star formation. While this galaxy's spiral pattern is not directly visible thanks to our side-on perspective, its disk is slightly warped, and there is clear evidence of star formation.

Along the full length of the galaxy, and scattered around parts of its halo, are bright pink nebulae. Similar to the Orion Nebula in the Milky Way, these are clouds of gas that are gradually coalescing into stars. The powerful radiation from the stars excites the gas and makes it light up, much like a fluorescent sign. The large number of these star formation regions is a telltale sign of gravitational interaction.

The dark filamentary structures that are scattered along the length of the galaxy are caused by cold interstellar dust blocking some of the starlight.

Read more at Science Daily

A Clock That Will Last Forever: Proposal to Build First Space-Time Crystal

Imagine a clock that will keep perfect time forever, even after the heat-death of the universe. This is the "wow" factor behind a device known as a "space-time crystal," a four-dimensional crystal that has periodic structure in time as well as space. However, there are also practical and important scientific reasons for constructing a space-time crystal. With such a 4D crystal, scientists would have a new and more effective means by which to study how complex physical properties and behaviors emerge from the collective interactions of large numbers of individual particles, the so-called many-body problem of physics.

A space-time crystal could also be used to study phenomena in the quantum world, such as entanglement, in which an action on one particle impacts another particle even if the two particles are separated by vast distances.

A space-time crystal, however, has only existed as a concept in the minds of theoretical scientists with no serious idea as to how to actually build one -- until now. An international team of scientists led by researchers with the U.S. Department of Energy (DOE)'s Lawrence Berkeley National Laboratory (Berkeley Lab) has proposed the experimental design of a space-time crystal based on an electric-field ion trap and the Coulomb repulsion of particles that carry the same electrical charge.

"The electric field of the ion trap holds charged particles in place and Coulomb repulsion causes them to spontaneously form a spatial ring crystal," says Xiang Zhang, a faculty scientist with Berkeley Lab's Materials Sciences Division who led this research. "Under the application of a weak static magnetic field, this ring-shaped ion crystal will begin a rotation that will never stop. The persistent rotation of trapped ions produces temporal order, leading to the formation of a space-time crystal at the lowest quantum energy state."

Because the space-time crystal is already at its lowest quantum energy state, its temporal order -- or timekeeping -- will theoretically persist even after the rest of our universe reaches entropy, thermodynamic equilibrium or "heat-death."

Zhang, who holds the Ernest S. Kuh Endowed Chair Professor of Mechanical Engineering at the University of California (UC) Berkeley, where he also directs the Nano-scale Science and Engineering Center, is the corresponding author of a paper describing this work in Physical Review Letters (PRL). The paper is titled "Space-time crystals of trapped ions." Co-authoring this paper were Tongcang Li, Zhe-Xuan Gong, Zhang-Qi Yin, Haitao Quan, Xiaobo Yin, Peng Zhang and Luming Duan.

The concept of a crystal that has discrete order in time was proposed earlier this year by Frank Wilczek, the Nobel-prize winning physicist at the Massachusetts Institute of Technology. While Wilczek mathematically proved that a time crystal can exist, how to physically realize such a time crystal was unclear. Zhang and his group, who have been working on issues with temporal order in a different system since September 2011, have come up with an experimental design to build a crystal that is discrete both in space and time -- a space-time crystal. Papers on both of these proposals appear in the same issue of PRL (September 24, 2012).

Traditional crystals are 3D solid structures made up of atoms or molecules bonded together in an orderly and repeating pattern. Common examples are ice, salt and snowflakes. Crystallization takes place when heat is removed from a molecular system until it reaches its lower energy state. At a certain point of lower energy, continuous spatial symmetry breaks down and the crystal assumes discrete symmetry, meaning that instead of the structure being the same in all directions, it is the same in only a few directions.

"Great progress has been made over the last few decades in exploring the exciting physics of low-dimensional crystalline materials such as two-dimensional graphene, one-dimensional nanotubes, and zero-dimensional buckyballs," says Tongcang Li, lead author of the PRL paper and a post-doc in Zhang's research group. "The idea of creating a crystal with dimensions higher than that of conventional 3D crystals is an important conceptual breakthrough in physics and it is very exciting for us to be the first to devise a way to realize a space-time crystal."

Just as a 3D crystal is configured at the lowest quantum energy state when continuous spatial symmetry is broken into discrete symmetry, so too is symmetry breaking expected to configure the temporal component of the space-time crystal. Under the scheme devised by Zhang and Li and their colleagues, a spatial ring of trapped ions in persistent rotation will periodically reproduce itself in time, forming a temporal analog of an ordinary spatial crystal. With a periodic structure in both space and time, the result is a space-time crystal.

"While a space-time crystal looks like a perpetual motion machine and may seem implausible at first glance," Li says, "keep in mind that a superconductor or even a normal metal ring can support persistent electron currents in its quantum ground state under the right conditions. Of course, electrons in a metal lack spatial order and therefore can't be used to make a space-time crystal."

Li is quick to point out that their proposed space-time crystal is not a perpetual motion machine because being at the lowest quantum energy state, there is no energy output. However, there are a great many scientific studies for which a space-time crystal would be invaluable.

"The space-time crystal would be a many-body system in and of itself," Li says. "As such, it could provide us with a new way to explore classic many-body questions physics question. For example, how does a space-time crystal emerge? How does time translation symmetry break? What are the quasi-particles in space-time crystals? What are the effects of defects on space-time crystals? Studying such questions will significantly advance our understanding of nature."

Peng Zhang, another co-author and member of Zhang's research group, notes that a space-time crystal might also be used to store and transfer quantum information across different rotational states in both space and time. Space-time crystals may also find analogues in other physical systems beyond trapped ions.

"These analogs could open doors to fundamentally new technologies and devices for variety of applications," he says.

Xiang Zhang believes that it might even be possible now to make a space-time crystal using their scheme and state of the art ion traps. He and his group are actively seeking collaborators with the proper ion-trapping facilities and expertise.

Read more at Science Daily

Castrated Men Outlive Other Guys

Castrated men tend to live much longer than fully endowed guys, according to a new study that suggests male sex hormones are responsible for shortening the lives of men.

The findings, published today in the journal Current Biology, could offer clues on how to extend the male lifespan. There might be a tradeoff of quantity versus quality, though.

The possible negative consequences of castration include "decreased libido, depression and loss of physical strength," according to coauthor Kyung-Jin Min of Inha University.

For the study, Min and colleague Cheol-Koo Lee, an associate professor in the College of Life Sciences and Biotechnology at Korea University, analyzed genealogy records of noble members of the Imperial court of the Korean Chosun dynasty (A.D. 1392-1910).

The castrated boys either lost their reproductive organs in accidents (such as after being bitten by a dog) or they underwent castration purposefully to gain access to the palace. Male rulers, in particular, felt they could trust eunuchs with their female family members and harems, if they had them. Eunuchs could marry, though, and often adopted children, including other castrated boys.

The researchers found that the eunuchs lived 14 to 19 years longer than other men did. Three even lived to 100 or more, a feat of longevity that remains relatively rare among men even today.

The effect wasn't just due to fine palace living either, since kings and other male members of the court had the shortest lifespans of all. The eunuchs also spent time both inside the palace and out.

"Since castration extends lifespan by reducing male sex hormones, we still believe that the effect would be the same today," Min told Discovery News. "In fact, castration was also performed in the early 1900s in a Kansas mental hospital. Castrated patients lived 13 years longer than intact patients, which is similar to (the results) of our study."

Min continued, "Testosterone is known to increase the incidence of coronary heart disease and reduce immune function in males."

Lee added that because of this immune function suppression, eunuchs could be better able to resist infections.

Read more at Discovery News

How to Make an 'Energy Efficient' Warp Drive

Our everyday experience of interstellar travel usually comes in the shape of the U.S.S. Enterprise zooming around the galaxy at warp speed. Unfortunately, the warp drive is primarily used as a tool by scriptwriters to condense the extreme interstellar distances into hour-long episodes. But there's a growing field of study that actually attaches some physics -- albeit rather "exotic" physics -- to superluminal (a.k.a. faster-than-light) travel.

Earlier this month, scientists and engineers were able to discuss their warp drive concepts at the 100 Year Starship Symposium in Houston, Texas, and there was some good news for sci-fi fans everywhere: the warp drive might not be as energy hungry as previous studies suggested.

Sonny White of NASA's Johnson Space Center presented his calculations on the energies required to travel faster than Einstein's famous speed limit: the speed of light. By White's reckoning, his design of starship -- that is "adjusted into more of a rounded doughnut, as opposed to a flat ring" and oscillates the warp intensity -- could be powered by the approximate mass-energy of the Voyager 1 space probe.

Although "the mass-energy of the Voyager 1 space probe" may not sound like much, if you convert the 722 kilogram Voyager mass into raw energy (using Einstein's famous mass-energy equivalence equation: E=mc2), White's warp drive would require 6.5x1019 Joules (65 exajoules) to create a warp bubble. That's nearly the entire annual energy consumption of the United States.

Clearly, this monstrous energy requirement isn't practical, but it's one heck of an improvement over previous estimates.

A Universe Of Energy

In 1994, physicist Miguel Alcubierre was widely credited to be the first to put some real physics into the warp drive. Although Star Trek would have us believe that you just need some dilithium crystals and a starship captain to point his finger, saying "Engage," Alcubierre discovered that the warp drive was theoretically possible, but it would need all the energy in the entire universe to function.

Alcubierre realized that for a spacecraft to travel faster than the speed of light -- something that Einstein's Special Theory of Relativity prohibits -- the spacecraft would need to somehow create a warp "bubble" around it. This would allow the spacecraft to be contained within its own region of spacetime. If the bubble can be controlled, then the light-speed limit can be exceeded in 'normal' space -- the spacecraft itself would be stationary whereas the bubble in spacetime will zip around at, effectively, infinite speed.

As described by Eric W. Davis, senior research physicist at the Institute of Advanced Studies in Austin, Texas, and co-author of Frontiers of Propulsion Science, the warp drive can be envisaged as a means of "surfing" through spacetime:

"Think of space as the ocean and Michael Phelps is a starship. He's propelled by fission or fusion rockets -- any kind of rocket -- but he's swimming vigorously, leaving planet Earth and he's going to swim all the way to Alpha Centauri, 4.3 light-years away. He's flailing his arms, kicking his feet, expending a great deal of energy and he can't go very fast ... the resistance of the ocean water is going to keep him limited to below the speed of light. Einstein's special theory says you can't go faster than light, you can't even reach it, but you can always stay less than (light-speed). Warp drive is a whole different matter. What you do is use "exotic energy" ... basically just a fancy word for vacuum energy. You're going to use some quantum energy from the vacuum and you're going to surround your starship with a bubble of this energy and it bends space -- it creates a surf effect. Michael Phelps is now standing on a surfboard and instead of swimming through space at less than the speed of light, he's surfing on space. Space is like the wave on the ocean water that surfs him to the beach faster than the speed of light." -- Eric Davis on "Attack of the Show"

Fill 'er Up with One Jupiter

Although Alcubierre's calculations showed that unimaginably huge amounts of energy would be needed to create this warp bubble, recently, Richard Obousy, co-founder and president of Icarus Interstellar (a key partner of the 100YSS), used our new understandings of quantum mechanics and applied them to the warp drive's 'bubble.'

Obousy's approach is to manipulate dark energy -- the mysterious force that appears to permeate the entire Universe, causing it to expand -- in such a way that extra dimensions (as predicted by string theory) can facilitate the creation of a bubble of spacetime.

"Given that extra dimensions have not yet experimentally been shown to exist, and the idea that dark energy is an artifact of these extra dimensions is somehow related to these dimensions is clearly highly theoretical," Obousy told Discovery News, "however it provides us with an interesting perspective from which to examine the problem."

Although this method would theoretically allow a Alcubierre-like solution to traveling faster than the speed of light, vast amounts of energy would still be needed -- the approximate mass-energy of Jupiter! -- but at least it's an improvement from the "all the energy in the Universe" solution.

Referring to White's work, Obousy continued: "The Jupiter calculation was purposefully created as an 'upper bound' to the problem, and I'm glad that the work performed by my colleagues has demonstrated ways to reduce the energy requirements down further."

Read more at Discovery News

Sep 23, 2012

Some Deadly Breast Cancers Share Genetic Features With Ovarian Tumors

The most comprehensive analysis yet of breast cancer shows that one of the most deadly subtypes is genetically more similar to ovarian tumors than to other breast cancers.

The findings, published online Sept. 23 in Nature, suggest that most basal-like breast tumors and ovarian tumors have similar genetic origins and potentially could be treated with the same drugs, says the study's co-leader Matthew J. Ellis, MD, PhD, the Anheuser-Busch Chair in Medical Oncology at Washington University School of Medicine in St. Louis. The other co-leader is Charles M. Perou, PhD, at the University of North Carolina.

Basal-like tumors account for about 10 percent of all breast cancers and disproportionately affect younger women and those who are African-American.

The new research is part of The Cancer Genome Atlas project, which brings together leading genetic sequencing centers, including The Genome Institute at Washington University, to identify and catalog mutations involved in many common cancers. The effort is funded by the National Institutes of Health (NIH).

"With this study, we're one giant step closer to understanding the genetic origins of the four major subtypes of breast cancer," says Ellis, who treats breast cancer patients at the Siteman Cancer Center at Barnes-Jewish Hospital and Washington University. "Now, we can investigate which drugs work best for patients based on the genetic profiles of their tumors. For basal-like breast tumors, it's clear they are genetically more similar to ovarian tumors than to other breast cancers. Whether they can be treated the same way is an intriguing possibility that needs to be explored."

Currently, for example, basal-like breast tumors often are treated like many other breast cancers, using anthracycline-based chemotherapy. But another of Ellis's studies recently showed that women with basal-like tumors don't benefit from these drugs, which also have severe side effects. At the very least, he says, the new data indicates that clinical trials should be designed to avoid the use of these drugs in basal-like tumors.

As part of the new research, a nationwide consortium of researchers analyzed tumors from 825 women with breast cancer. The scientists used six different technologies to examine subsets of the tumors for defects in DNA, RNA (a close chemical cousin of DNA) and proteins. Nearly 350 tumors were analyzed using all six technologies.

"By tying together those different data sets, we can build a story around the biology of each breast cancer subtype that is dictated by the genome, interpreted by the RNA and played out by the proteins at work inside each tumor," says co-author Elaine Mardis, PhD, co-director of The Genome Institute. "These data can serve as a backdrop for other questions about how particular mutations affect survival or response to certain drugs."

The study confirmed the existence of four main subtypes of breast cancer: Luminal A, luminal B, HER2 and basal-like. The latter includes most triple-negative breast tumors, so-named because they lack receptors for the hormones estrogen, progesterone or human epidermal growth factor 2 (HER2). These tumors often are aggressive and do not respond to therapies that target hormone receptors or to standard chemotherapies.

Across the four subtypes, mutations in only three genes -- TP53, PIK3CA and GATA3 -- occurred in more than 10 percent of patients' tumors. But, the scientists found unique genetic and molecular signatures within each of the subtypes. Their findings add to the growing body of evidence suggesting that tumors should be cataloged and treated based on the genes that are disrupted rather than the location in the body.

In general, compared to the other subtypes, basal-like and HER2 tumors had the highest mutation rates but the shortest list of significantly mutated genes. These genes are thought to be major drivers of cancer progression. For example, 80 percent of basal-like tumors had mutations in the TP53 gene, which have been linked to poor outcomes. About 20 percent of the tumors also had inherited mutations in BRCA1 or BRCA2 genes, which are known to increase the risk of breast and ovarian cancer.

"This suggests that it only takes a few hits to key genes that drive cancer growth," Mardis explains.

A high frequency of TP53 mutations also occurs in ovarian cancer, the researchers noted. Overall, the genetic profiles of basal-like and ovarian tumors were strikingly similar, with widespread genomic instability and mutations occurring at similar frequencies and in similar genes.

Finding new drug targets for basal-like breast tumors is critical, and the research suggests that patients with mutations in the BRCA genes may benefit from PARP inhibitors or platinum-based chemotherapy, which are already used to treat ovarian cancer.

By comparison, luminal cancers (which include estrogen receptor-positive and progesterone-receptor positive tumors) had the lowest mutation frequencies and longer lists of significantly mutated genes. This suggests defects in multiple genetic pathways can lead to the development of luminal breast cancers.

Most patients with luminal A cancer have good outcomes, and the most common mutation in that subtype occurred in PIK3CA, which was present in 45 percent of tumors. TP53 mutations only occurred in 12 percent.

Some patients with luminal B tumors do well but many experience recurrence years after treatment. Interestingly, the most common mutations in these tumors occurred in TP53 (linked to poor outcomes) and PIK3CA (linked to good outcomes), which may explain the disparate results seen in patients with this subtype.

Read more at Science Daily

Search for Mysterious Lost Da Vinci Aborted

A longstanding Leonardo da Vinci mystery -- the fate of a lost masterpiece known as the Battle of Anghiari –- will remain unsolved.

The ambitious project to find the long-lost artwork has been put on indefinite hold and the massive scaffolding erected for the hunt will be dismantled at the end of the month.

The scaffoldings have been standing for nearly 10 months in front of a frescoed wall in Palazzo Vecchio, Florence's 14th-century city hall, in the imposing Hall of Five Hundred. This was a room built at the end of the 15th century to accommodate the meetings of the Florentine Council.

Right there, behind a mural known as the "Battle of Marciano," would lie Da Vinci's masterpiece, according to art diagnostic expert Maurizio Seracini, director of the Center of Interdisciplinary Science for Art, Architecture and Archaeology at the University of California, San Diego.

Created by the renowned 15th-century painter, architect and writer Giorgio Vasari (1511-1574), the mural has been at the center of Seracini’s research since the 1970s.

 Finally, in late 2011, Seracini identified 14 small areas in the frescoed wall that could be explored by endoscopy and asked for permission to investigate them.

Italy’s culture minister granted authorization to work in seven areas, leaving the decision of where to insert the endoscopic probe to the local superintendency and the Opificio delle Pietre Dure (OPD) art restoration laboratory.

To ensure that no damage would be done to Vasari’s mural, areas were chosen that were either free of original Vasari paint or were cracked or previously restored.

In January, Seracini's team drilled six tiny holes into Vasari's fresco, inserted a 0.15-inch-wide probe and micro-cameras and collected samples of red, white, orange and black material.

"None of the six points of entry chosen by the Opificio Delle Pietre Dure was among the 14 original points identified by Prof. Seracini. Nevertheless, he and his scientific team were encouraged by the results," said National Geographic, who sponsored the Battle of Anghiari Project, in a statement.

Indeed, analysis with a scanning electron microscope revealed the black material had an unusual chemical makeup of manganese and iron. 

According to Seracini, the compound corresponded to the black pigment found in brown glazes on Leonardo's "Mona Lisa" and"'St. John the Baptist."

Red material, most likely red lacquer, was also found. Moreover, high-definition endoscopic images revealed a beige material that "could only have been applied by a paint brush," the researcher said.

According to Seracini, the endoscopy also provided visual evidence of an air gap, previously identified by radar scanning, between The Battle of Marciano and the wall behind it. This would suggest that Vasari created it intentionally to preserve Leonardo’s masterpiece, he said.

The hypothesis added more intrigue to Leonardo Da Vinci’s lost masterpiece.

Described as "the great mystery story of the Renaissance" by the mayor of Florence Matteo Renzi, the Battle of Anghiari was conceived in 1503, when Leonardo and Michelangelo received twin commissions to paint historic Florentine victories on opposite walls of the Palazzo Vecchio in Florence.

While Michelangelo never got past a sketch of his "Battle of Cascina," Leonardo began to paint the centerpiece of the ''Battle of Anghiari," known as the ''Fight for the Standard," on June 6, 1505, when he was 53.

"Representing vividly the rage and fury both of the men and the horses," as Vasari wrote in his 1550 book "Lives of the Artists," the 12- by 15-foot mural would celebrate the Florentine's victory over Milanese troops in 1440.

Vasari reported that Leonardo abandoned the project because of technical problems arising from his experimental mixing of oil paint and fresco.

Historians, however, have questioned his conclusion. Some speculated that Vasari made up the story, and that the fresco actually was completed.

Hailed by Leonardo's contemporaries as his finest work, the "Battle of Anghiari" now survives in several preparatory drawings and sketches by the master himself and in a Rubens drawing which was inspired by an anonymous copy of the fresco.

Ten years after writing his account of the "Battle of Anghiari," Vasari was hired to modify the council room into the Hall of Five Hundred, a hall dedicated to the ruling Medici family. In the course of this work, Leonardo's mural disappeared.

It wasn't the only artwork to dissolve.

Working on the city-wide renovation plan devised by Duke Cosimo I to celebrate the Medici family, Vasari had to sacrifice masterpieces such as Masaccio's Trinity in the church of Santa Maria Novella.

Yet he did not destroy the work; he just bricked it over and added his own fresco, the "Madonna of the Rosary."

Masaccio's work remained obscured until 1861, when Vasari's wall was removed.

In 2000, at a Da Vinci conference, leading scholar Carlo Pedretti proposed that Vasari saved Leonardo's masterpiece just as he had Masaccio's.

The conference prompted Seracini to carry out sophisticated tests that involved the use of laser scanners, X-ray machines, and thermographic and radar equipment.

The only nonfictional living character mentioned in "The Da Vinci Code," Seracini found a Dan Brown-like clue in the wall housing the "Battle of Marciano." There, on a tiny painted green flag, Vasari wrote: "Cerca, trova -- seek and you shall find."

The intriguing traces of paint found behind Vasari’s fresco represented  "an historic result, a mile stone," according to Renzi.

However, to continue their work, researchers required more sophisticated chemical exams such as tomography by XRD/XRF at the European Synchrotron Radiation Facility, in Grenoble, France.

Renzi recently requested permission from the Italian authorities to resume and bring to completion the research, but a controversy had already sprung up over the intrusive approach.

Cecilia Frosinini, mural paintings section director at the Opificio, immediately resigned in protest from the project.

"It's an ethical question. I'm supposed to protect the artworks, and here there is an invasive intervention on the painting," Frosinini wrote.

Following her reaction, many art historians signed a petition asking to stop the drilling and even questioning the possibility that the fresco was indeed hidden behind Vasari’s mural.

"Vasari would have never covered a work by an artist he admired so much in the hope that one day someone would search and find it. You would expect such a hypothesis from Dan Brown, certainly not from art historians," Tomaso Montanari, an art historian at the University Federico II in Naples, said.

This summer, the saga of the lost Da Vinci’s fresco took its final twist.

Cristina Acidini, superintendent for the Polo Museale Fiorentino, replied to Renzi by authorizing the endoscopic investigation of a seventh hole in a paint-free area originally identified by the OPD, but ruled out the possibility of carrying out futher holes as requested by the scientific team.

Read more at Discovery News