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As modern cosmologists rely more and more on the ominous “dark matter” to explain otherwise inexplicable observations, much effort has gone into the detection of this mysterious substance in the last two decades, yet no direct proof could be found that it actually exists. Even if it does exist, dark matter would be unable to reconcile all the current discrepancies between actual measurements and predictions based on theoretical models. Hence the number of physicists questioning the existence of dark matter has been increasing for some time now. Competing theories of gravitation have already been developed which are independent of this...

Three educators give their views on exams Susan Greenfield, professor of synaptic pharmacology at Lincoln College, Oxford, and director of the Royal Institution "Back when I went to Oxford, the entrance exams for women were different. The one for Oxford I found most challenging was the general classics paper. It was a 3.5 hour paper – you had half an hour to think ,then one hour for each question. I still remember one of the questions – 'compare the ideas of empire in Greece and Rome'. That was a real high jump intellectually. Exams are good things. They prepare you...

Astronomers have turned up the oldest and most distant supernova ever found: the star that created it detonated just 3 billion years after the big bang. The technique used to find it could reveal tens of thousands of other ancient supernovae, tracing out how the universe became seeded over time with heavy elements. Because light travels at a finite speed, more distant supernovae also occur further back in time. The calculated distance of the newly discovered blast suggests it occurred 10.7 billion years ago – about 1.5 billion years earlier than the previous record holder. The new blast was a...

The orbit of the innermost planet, Mercury, departs from what it should be under Newton's laws. A century ago, when Einstein explained this anomaly, it confirmed his theory of gravity - the general theory of relativity. Now an Israeli physicist predicts that a similar but far more subtle anomaly in the orbits of the planets, if detected, might prove his own theory, known as modified Newtonian dynamics, or MOND. This provides an alternative theory to dark matter to explain why stars orbiting at the edge of spiral galaxies are not flung out into space. These stars are travelling at speeds...

Did dark matter destroy the universe? You might be looking around at the way things "exist" and thinking "No", but we're talking about ancient history. Three hundred million years after the start of the universe, things had finally cooled down enough to form hydrogen atoms out of all the protons and electrons that were zipping around - only to have them all ripped up again around the one billion year mark. Why? Most believe that the first quasars, active galaxies whose central black holes are the cosmic-ray equivalent of a firehose, provided the breakup energy, but some Fermilab scientists have...

If the universe obeyed Newton's laws of gravity, there would be about a 60% chance that Mercury would head toward the Sun or Venus during the Sun’s lifetime. But according to a new study, corrections to Newton's laws using Einstein's theory of gravity (general relativity) lower these chances to about 1%. That’s good news, because if Mercury had a near miss with Venus or the Sun, it could wreak havoc on Earth.

Enlarge ImageOutlier. Astronomers think they have found an intermediate-mass black hole (bright blue object) just outside a distant galaxy. Credit: Heidi Sagerud Heavyweight and lightweight black holes abound in the universe, but nobody has detected a middleweight--and some scientists argue they don't exist. Now, astronomers say they have found the first conclusive evidence for one of these elusive objects at the fringe of a distant galaxy. Estimated to be at least 500 times more massive than the sun, the discovery could plug a large gap in the cosmic menagerie, though it leaves unanswered questions about this type of black...

Borrowing from the physics of invisibility cloaks could make it possible to hide buildings from the devastating effects of earthquakes, say physicists in France and the UK. The "earthquake cloak" idea comes from the team led by Stefan Enoch at the Fresnel Institute in Marseille, France. They were the first to show that the physics of invisibility cloaks could have other applications – designing a cloak that could render objects "invisible" to destructive storm waves or tsunamis. The seismic waves of an earthquake fall into two main groups: body waves that propagate through the Earth, and surface waves that travel...

Fission and quarks figure into quirky caseIt's not every day that disputes over particle physics leads to assault charges. But that's what happened when Jason Everett Keller, 40, joined a conversation about quantum physics in South San Francisco in March. Keller was accused of attacking Stephan Fava while Fava and his friend were discussing physics in the Bay Area town. The charges didn't stick, however, as Keller has been acquitted by a San Mateo County jury. The verdict is still out string theory, however, so there's no indication that physics-related violence will abate any time soon. Related Stories Jackson West...

New data show that enrollment in U.S. science and engineering (S&E) graduate programs in 2007 grew 3.3 percent over comparable data for 2006--the highest year-over-year increase since 2002 and nearly double the 1.7 percent increase seen in 2006. Science programs added the most students in absolute numbers, but engineering's percentage growth over 2006, 5.9 percent, was substantially higher than that of science, which grew by 2.4 percent. Enrollment in computer sciences programs was up 2.7 percent, the first increase since 2002. The proportion of foreign students enrolled in S&E graduate programs in 2007 remained below its 2002 high, despite a...

"Star Trek" makes faster-than-light travel look easy, but according to new calculations by Italian physicists, a warp drive could easily create a black hole that would incinerate any passengers on a space craft and then suck Earth into a black hole. "Warp drives are so far the best case scenario to attain faster-than-light travel," said Stefano Finazzi of Italy's International School for Advanced Studies. This paper "makes it much harder to realize, if not almost impossible, warp drives." ...Other physicists agree with the Italians' calculations, up to a point. "It's a good paper; their results are sound," said Gerald Cleaver,...

How our youthful universe explored the string-theory multiverse in search of home—with help from its anti-universe counterpart. Its journey could explain why our cosmos is so well suited for life.Saswat Sarangi owes his career in physics to a twist of fate. When he was a 13 year-old schoolboy in Orissa in eastern India, his uncle bought him a copy of Stephen Hawking’s A Brief History of Time as a birthday present. Unfortunately, the young Sarangi would have preferred a cricket bat, and the book remained unread for two years, until he found himself struggling to prepare for a physics test...

GENEVA (AP) — The world's largest atom smasher will likely be fired up again in October after scientists have carried out tests and put in place further safety measures to prevent a repeat of the faults that sidelined the $10 billion machine shortly after startup last year, the operator said Saturday. The Large Hadron Collider was meant to restart in late September, but that will probably be pushed back two to three weeks, a spokesman for the European Organization for Nuclear Research said. "We're pretty confident about the dates," James Gillies told The Associated Press, adding that scientists believe they...

A dispatch from my colleague Dennis Overbye: As fans of the late, great “Seinfeld,” know, there is a lot to say about nothing. At the World Science Festival Thursday night, four physicists spent nearly two hours under the jocular and irreverent grilling radio broadcaster John Hockenberry, cohost of “The Takeaway,” and barely scratched the surface of the void that is the background or perhaps the platform of all our experience. They did in the end offer an answer to the question that has plagued philosophers and scientists: Why is there something rather than nothing at all? “Nothing is unstable,” Frank...

Nanoscience milestone opens up new possibilities in molecular electronics ZURICH, June 12 /PRNewswire-FirstCall/ -- IBM (NYSE: IBM) scientists in collaboration with the University of Regensburg, Germany, and Utrecht University, Netherlands, for the first time demonstrated the ability to measure the charge state of individual atoms using noncontact atomic force microscopy. View video: http://www.youtube.com/watch?v=plMkPtwEMRM (Logo: http://www.newscom.com/cgi-bin/prnh/20090416/IBMLOGO ) Measuring with the precision of a single electron charge and nanometer lateral resolution, researchers succeeded in distinguishing neutral atoms from positively or negatively charged ones. This represents a milestone in nanoscale science and opens up new possibilities in the exploration of nanoscale structures and...

Re-Analysis of the Marinov Light-Speed Anisotropy Experiment Reginald T. Cahill School of Chemistry, Physics and Earth Sciences, Flinders University, Adelaide 5001, Australia E-mail: Reg.Cahill@flinders.edu.au The anisotropy of the speed of light at 1 part in 10^3 has been detected by Michelson and Morley (1887), Miller (1925/26), Illingworth (1927), Joos (1930), Jaseja et al. (1964), Torr and Kolen (1984), DeWitte (1991) and Cahill (2006) using a variety of experimental techniques, from gas-mode Michelson interferometers (with the relativistic theory for these only determined in 2002) to one-way RF coaxial cable propagation timing. All agree on the speed, right ascension and declination of...

BERLIN (Reuters) – A new, superheavy chemical element numbered 112 will soon be officially included in the periodic table, German researchers said. A team in the southwest German city of Darmstadt first produced 112 in 1996 by firing charged zinc atoms through a 120-meter-long particle accelerator to hit a lead target. "The new element is approximately 277 times heavier than hydrogen, making it the heaviest element in the periodic table," the scientists at the GSI Helmholtz Center for Heavy Ion Research said in a statement late on Wednesday.

Claims of bias against women in academic science have been greatly exaggerated. Meanwhile, men are becoming the second sex in American higher education.In 2006 the National Academy of Sciences released Beyond Bias And Barriers: Fulfilling the Potential of Women in Academic Science and Engineering, which found “pervasive unexamined gender bias” against women in academic science. Donna Shalala, a former Clinton administration cabinet secretary, chaired the committee that wrote the report. When she spoke at a congressional hearing in October 2007, she warned that strong measures would be needed to improve the “hostile climate” women face in university science. This “crisis,”...

BERLIN (Reuters) – A new, superheavy chemical element numbered 112 will soon be officially included in the periodic table, German researchers said. A team in the southwest German city of Darmstadt first produced 112 in 1996 by firing charged zinc atoms through a 120-meter-long particle accelerator to hit a lead target. "The new element is approximately 277 times heavier than hydrogen, making it the heaviest element in the periodic table," the scientists at the GSI Helmholtz Center for Heavy Ion Research said in a statement late on Wednesday.

Enlarge ImageSpooky connection. Physicists forged a quantum link called entanglement between the mechanical oscillations of one pair of ions and another distant pair. Credit: John Jost and Jason Amini/NIST Quantum mechanics and its bizarre rules explain the structure of atoms, the formation of chemical bonds, and the switching of transistors in microchips. Oddly, though, in spite of the theory's name, physicists have never made an actual machine whose motion captures the quirkiness of quantum mechanics. Now a group from the National Institute of Standards and Technology (NIST) in Boulder, Colorado, has taken a step in that direction by forging...