Tuesday, January 29, 2013

What, exactly, is a Calabi-Yau manifold?

String theory describes one of the smallest things you can possibly imagine — six-dimensional geometric spaces that may be more than a trillion times smaller than an electron — that could be one of the defining features of our universe. The story of these spaces, can be explained by what physicists call “Calabi-Yau manifolds,”

Superstring theory is a unified theory for all the forces of nature including quantum gravity. In superstring theory, the fundamental building block is an extended object, namely a string, whose vibrations would give rise to the particles encountered in nature. The constraints for the consistency of such a theory are extremely stringent. They require in particular that the theory takes place in a 10-dimensional space-time. To make contact with our 4-dimensional world, it is expected that the 10-dimensional space-time of string theory is locally the product M 4 ×X of a 4-dimensional Minkowski space M 3,1 with a 6-dimensional space X . The 6-dimensional space X would be tiny, which would explain why it has not been detected so far at the existing experimental energy levels. Each choice of the internal space X leads to a different effective theory on the 4-dimensional Minkowski space M 3,1 , which should be the theory describing our world.

It has long been argued that, in order to solve certain classic problems of unified gauge theories such as the gauge hierarchy problem, the 4-dimensional effective theory should admit an N=1 supersymmetry. In a fundamental paper, Candelas, Horowitz, Strominger and Witten (1985) analyzed what the constraint of that N=1 supersymmetry would mean for the geometry of the internal space X . They found that, for the most basic product models with N=1 supersymmetry, the space X must be a Calabi-Yau manifold of complex dimension 3. Shortly afterwards, Strominger (1986) considered slightly more general models, allowing warped products. For these models, the N=1 supersymmetry constraint results in a modification of the Ricci-flat equation of the earlier model.

Friday, August 3, 2012

Why women live longer?

The answer to the mystery of why women tend to live longer than men was found in the mitochondrial DNA studies of fruit flies.

Mitochondria are inherited only from mothers, never from fathers, so there is no way to weed out mutations that damage a male's prospects.

But one ageing expert said there were many factors that explained the gender difference in life expectancy.

It is not only in human, females outlive males in many other species.

Mitochondria, which exist in almost all animal cells, convert food into the energy that powers the body.

Group of scientists from Monash University found numerous mutations within mitochondrial DNA that affect how long males live, and the speed at which they age. Mitochondrial mutations they uncovered will generally cause faster male ageing across the animal kingdom.

They suggested this is because there is no evolutionary reason for the faults that affect males to be picked up - because mitochondria are passed down by females.

Thursday, July 5, 2012

Higgs Boson- the God particle.

Lot of news is pouring about Higgs Boson- the God particle after European Center for Nuclear Research says its teams have discovered a new particle that is consistent with the Higgs boson -- a subatomic particle considered so significant to the understanding of the universe that it has been called the God particle.

So what's the Higgs boson?

The Higgs particle, and its associated field, were hypothesized back in the 1960s by British physicist Peter Higgs and others to fill a weird gap in the Standard Model, one of physics' most successful theories. The model as it stood had no mechanism to explain why some particles are massless (such as the photon, which is the quantum bit for light and other types of electromagnetic radiation), while other particles have varying degrees of mass (such as the W and Z bosons, which play a part in the weak nuclear force). By rights, all particles should be without mass and zipping around freely.

They suggested that all particles had no mass just after the Big Bang. As the Universe cooled and the temperature fell below a critical value, an invisible force field called the ‘Higgs field’ was formed together with the associated ‘Higgs boson’. The field prevails throughout the cosmos: any particles that interact with it are given a mass via the Higgs boson. The more they interact, the heavier they become, whereas particles that never interact are left with no mass at all.

This idea provided a satisfactory solution and fitted well with established theories and phenomena. The problem is that no one has ever observed the Higgs boson in an experiment to confirm the theory. Finding this particle would give an insight into why particles have certain mass, and help to develop subsequent physics. The technical problem is that we do not know the mass of the Higgs boson itself, which makes it more difficult to identify. Physicists have to look for it by systematically searching a range of mass within which it is predicted to exist. The yet unexplored range is accessible using the Large Hadron Collider, which will determine the existence of the Higgs boson. If it turns out that we cannot find it, this will leave the field wide open for physicists to develop a completely new theory to explain the origin of particle mass.

The international effort to find it has used tremendous amounts of energy to crash subatomic particles into one another in giant underground tracks, where they are steered by magnetic fields. Several different experiments have been done by independent teams to ensure accuracy.

It is believed that Fermilab's atom smasher, called the Tevatron, must have produced thousands of Higgs particles over its life before it was shut down last year after it was overshadowed by CERN's more powerful Large Hadron Collider.

Two independent teams at CERN, the physics lab in the Alps on the French-Swiss border, have now said that they have "observed" the new boson, or subatomic particle. The CERN teams did not outright say that they have discovered the Higgs boson itself, which has been the focus of a 40-plus year pursuit.

Tuesday, March 6, 2012

Asteroid Threat in 2040???

There is an asteroid called 2011 AG5, and if it follows the orbit scientists have plotted for it so far, there is a small, small chance that it could hit Earth in February 2040. Astronomers, who have been tracking the asteroid since January 2011, say it is in an elliptical orbit that could bring it somewhere near Earth in 2040. Earth is about 8,000 miles in diameter; the asteroid appears to be about 450 feet across.
The problem is that having watched it for only about half an orbit around the Sun, the scientists cannot say for certain where it will be 28 years from now. So, for the moment, NASA's Near Earth Object Program says the odds are about one in 625 that it could hit us in that still-distant future.
Scientists have discussed all sorts of far-out plans in case a future asteroid truly does turn out to be coming our way. If they have enough lead time, they might send a probe with thruster rockets, or even explosives, to nudge an asteroid into a slightly different orbit. A very small course change, years in advance, could make a big difference by 2040, they say. Even if the asteroid misses Earth by less than a hundred miles, its passing will be a non-event.

There are asteroids wandering around the inner solar system all the time -- one of them, called 2005 YU55, passed within 201,000 miles of Earth in November, closer than the moon is to us.
But about half a dozen times since the planet formed, there have been major for-real impacts with catastrophic results. The last, 65 million years ago, is believed to have killed off the last of the dinosaurs with the dust and ash that darkened the skies after it hit, though there have been scientists who disagree.
Scientists estimate that the asteroid from back then was about nine miles across at its widest, far larger than 2011 AG5. And they point out that they know very little about 2011 AG5; they cannot say whether it is a solid hunk of rock or a loose jumble of debris flying together in space. All they know is that it's in a long, elliptical orbit that takes it almost twice as far from the sun as we are.

Wednesday, February 15, 2012

All about Curveball

The curveball is a type of pitch in baseball thrown with a characteristic grip and hand movement that imparts forward spin to the ball causing it to dive in a downward path as it approaches the plate.

Generally the Magnus effect describes the laws of physics that make a curveball curve. A fastball travels through the air with backspin, which creates a higher pressure zone in the air ahead of and under the baseball. The baseball's raised seams augment the ball's ability to churn the air and create higher pressure zones. The effect of gravity is partially counteracted as the ball rides on and into energized air. Thus the fastball falls less than a ball thrown without spin (neglecting knuckleball effects) during the 60 feet 6 inches it travels to home plate.

The Magnus effect is the phenomenon whereby a spinning object flying in a fluid creates a whirlpool of fluid around itself, and experiences a force perpendicular to the line of motion. The overall behaviour is similar to that around an airfoil (see lift force) with a circulation which is generated by the mechanical rotation, rather than by aerofoil action.

In many ball sports, the Magnus effect is responsible for the curved motion of a spinning ball. The effect also affects spinning missiles, and is used in rotor ships and Flettner aeroplanes.

In order to watch this science experiment on the basball field go see St. Louis cardinals or the Los Angeles Angels this season. Here are links to buy your ticket through Ticketamerica.com

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los angeles angels of anaheim tickets
minnesota twins tickets

Wednesday, February 8, 2012

Russia reaches Lake Vostok, about 3.8 kilometers (2.4 miles) beneath the Antarctica Surface

After more than two decades of drilling, Russian scientists have reached the surface of a gigantic freshwater lake in Antarctica that had been hidden under miles of ice for 20 million years, potentially holding life from the distant past and a clue to the search for life on other planets.

Reaching Lake Vostok is a major discovery avidly anticipated by scientists around the world hoping that it may allow a glimpse into microbial life forms that existed before the Ice Age. It may also provide precious material that would help look for life on ice-crust moons of Jupiter and Saturn or under Mars' polar ice caps where conditions could be similar.

The project, however, has drawn strong fears that 60 metric tons (66 tons) of lubricants and antifreeze used in the drilling may contaminate the pristine lake. The Russian researchers have insisted that the bore would only slightly touch the lake's surface and a surge in pressure will send the water rushing up the shaft where it will freeze, immediately sealing out the toxic chemicals.

Lukin said in a statement that about 1.5 cubic meters of kerosene and freon poured into tanks on the surface from the boreshaft, proof that the lake water streamed from beneath, froze, and blocked the hole.

The scientists will later remove the frozen sample for analysis in December when the next Antarctic summer comes.

Lake Vostok, about 3.8 kilometers (2.4 miles) beneath the surface, is the largest in a web of nearly 400 known subglacial lakes in Antarctica, and scientists in other nations hope to follow up with similar projects. The lake is 250 kilometers (160 miles) long and 50 kilometers (30 miles) across at its widest point, similar in area to Lake Ontario.

Scientists believe that microbial life may exist in the dark depths of the lake despite high pressure and constant cold — conditions similar to those expected to be found under ice crust on Mars, Jupiter's moon Europa and Saturn's move Enceladus.

Tuesday, December 6, 2011

New Earth-like Planet: Kepler-22b

NASA's Kepler space telescope has found a new planet -- the most Earth-like yet -- circling a yellow star similar to Earth's sun and 600 light-years away, according to the space agency.

The most promising thing about this world, called Kepler-22b for now is that it's in the so-called Goldilocks zone around its host star. Its surface temperature is estimated at an average of 72 degrees, which means liquid water -- considered essential for life as we know it -- would be possible there.

But just how realistic are the prospects for life on that distant world? Even in their excitement, the researchers caution that they have found no proof that we are not alone.

The Kepler team has done a prodigious job of detection and mathematical calculation, but Kepler has not actually seen the planet or taken any chemical measurements. They know its host star is slightly smaller and cooler than the sun, and they found that its light dims ever so slightly once every 290 Earth days. That means the dot of the planet is passing in front of it. It's a little closer to its sun than we are to our sun.

From there, they can extrapolate. For the planet to be in a nice, nearly circular orbit, not too hot and not too cold, they figured out that it's probably 2.4 times the diameter of Earth.

That makes it among the smallest planets yet found orbiting other stars, but it's a smidgen larger than an ideal candidate for extraterrestrial life would be.

"That smidgen makes all the difference," said Geoff Marcy of the University of California, Berkeley, who is one of the pioneers of planet-hunting outside Earth's solar system, and a member of the Kepler team.

Scientists know, from looking at Earth's solar system, that rocky worlds like the Earth's are a precious commodity. If a world is too small (think of Mercury or Earth's moon), any atmosphere will escape into space before life could possibly form. If a world is too large (think of Jupiter or Neptune) it's likely to be all atmosphere, a giant ball of gas or slush that thickens quickly as you plunge beneath its cloud tops, but probably has no solid surface where living things could thrive.

Kepler-22b might be the right temperature, but it is probably closer in mass to icy Neptune than to Earth. "I would bet my telescope that there is no hard, rocky surface to walk on," Marcy told the Associated Press.

Still, the discovery sets scientists' minds racing. "This discovery shows that we Homo sapiens are straining our reach into the universe to find planets that remind us of home," Marcy said. "We are almost there."
Thanks to Associated Press for using there new release.

Wednesday, November 23, 2011

Euphoria for "faster than light" particle didn't last much

An international team of scientists in Italy studying the same neutrino particles colleagues say appear to have travelled faster than light rejected the startling finding this weekend, saying their tests had shown it must be wrong.

The September announcement of the finding, backed up last week after new studies, caused a furor in the scientific world as it seemed to suggest Albert Einstein's ideas on relativity, and much of modern physics, were based on a mistaken premise.

The first team, members of the OPERA experiment at the Gran Sasso laboratory south of Rome, said they recorded neutrinos beamed to them from the CERN research center in Switzerland as arriving 60 nanoseconds before light would have done.

But ICARUS, another experiment at Gran Sasso -- which is deep under mountains and run by Italy's National Institute of National Physics -- now argues that their measurements of the neutrinos energy on arrival contradict that reading.

In a paper posted Saturday on the same website as the OPERA results, arxiv.org/abs/1110.3763v2, the ICARUS team says their findings "refute a superluminal (faster than light) interpretation of the OPERA result."

They argue, on the basis of recently published studies by two top U.S. physicists, that the neutrinos pumped down from CERN, near Geneva, should have lost most of their energy if they had travelled at even a tiny fraction faster than light.

But in fact, the ICARUS scientists say, the neutrino beam as tested in their equipment registered an energy spectrum fully corresponding with what it should be for particles traveling at the speed of light and no more.

Physicist Tomasso Dorigo, who works at CERN, the European Organization for Nuclear Research, and the U.S. Fermilab near Chicago, said in a post on the website Scientific Blogging that the ICARUS paper was "very simple and definitive."

It says, he wrote, "that the difference between the speed of neutrinos and the speed of light cannot be as large as that seen by OPERA, and is certainly smaller than that by three orders of magnitude, and compatible with zero."

Under Einstein's 1905 theory of special relativity, nothing can travel faster than light. That idea lies at the heart of all current science of the cosmos and of how the vast variety of particles that make it up behave.

There was widespread skepticism when the OPERA findings were first revealed, and even the leaders of the experiment insisted that they were not announcing a discovery but simply recording measurements they had made and carefully checked.

However, last Friday they said a new experiment with shorter neutrino beams from CERN and much larger gaps between them had produced the same result. Independent scientists said however this was not conclusive.

Other experiments are being prepared -- at Fermilab and at the KEK laboratory in Japan -- to try to replicate OPERA's findings. Only confirmation from one of these would open the way for a full scientific discovery to be declared.

Tuesday, October 18, 2011

Antimicrobial Sorption Materials-VitaVallis

Russian scientists have developed a drug-free method of healing wounds that may prove as revolutionary as the discovery of penicillin.

Antimicrobial sorption materials –VitaVallis is safe alternative to antibiotics and chemicals for healing wounds and wound infections, including antibiotic resistant ones. VitaVallis, created by researchers in Tomsk, Siberia, helps clean up wounds of all known types of toxic bacteria. It does not get stuck to the wound and heals burns, cuts and any septic and infected wounds two to three times faster than traditional methods do. The dressing stops bleeding, ends inflammation, eliminates swellings and stimulates skin regeneration. It also helps kill pain and remove foul wound odour.

The new method was developed at the junction of physics and medicine. It is based on the long-known fact that pathological bacteria typically carry a negative electric charge. Siberian researchers figured that positively charged material should be able to extract bacteria from wounds.

The secret of the VitaVallis antiseptic dressing is the positively charged nanosized alumina fibre which drags negatively charged microbes and lock them down in the absorbing layer.

Check out more at http://vitavallis.com/eng/main.html