Long before Mercury, Venus, Earth, and Mars formed, it seems that the inner solar system may have harbored a number of super-Earths—planets larger than Earth but smaller than Neptune. If so, those planets are long gone—broken up and fallen into the sun billions of years ago largely due to a great inward-and-then-outward journey that Jupiter made early in the solar system's history.
This possible scenario has been suggested by Konstantin Batygin, a Caltech planetary scientist, and Gregory Laughlin of UC Santa Cruz in a paper that appears the week of March 23 in the online edition of the Proceedings of the National Academy of Sciences (PNAS). The results of their calculations and simulations suggest the possibility of a new picture of the early solar system that would help to answer a number of outstanding questions about the current makeup of the solar system and of Earth itself. For example, the new work addresses why the terrestrial planets in our solar system have such relatively low masses compared to the planets orbiting other sun-like stars.
Dark matter 'ghosts' through galactic smash-ups
Dark matter is the mysterious, invisible stuff that makes up 85% of the matter in the cosmos - and these results rule out several theoretical models put forward to explain it. This is because it barely interacts with anything at all, including the dark matter in the oncoming galaxies.
The work appears in Science magazine.
Astronomers Discover Dwarf Galaxies Orbiting the Milky Way
Astronomers have discovered a ‘treasure trove’ of rare dwarf satellite galaxies orbiting our own Milky Way. The discoveries could hold the key to understanding dark matter, the mysterious substance which holds our galaxy together.
Terraforming Mars by Polluting its Atmosphere
Four University of Leicester physics students have co-written a paper which highlights a problematic concept when planning a human colony on Mars. Colonizing the Red Planet is exactly the kind of goal that the privately funded Mars One program me has set for itself and hopes to achieve by 2025. It has recently announced the penultimate stage of its colonist selection program.
So undergraduates Alex Longman, 22, Kieran Flatt, 21, Sam Turnpenney, 32, and Maria Garreffa, 22, got together to look at the possibility of terraforming Mars in preparation for its first human settlers. As part of a course module which invites them to consider alternative and off-the-wall suggestions based on real scientific principles, the groups looked at burning copious amounts of coal on Mars to create enough carbon dioxide to alter the Martian atmosphere. The process would increase the atmospheric density and eliminate the need for pressurized spacesuits making the Red Planet more habitable. However, the group performed some short calculations to demonstrate that, unsurprisingly, there are some major difficulties with this proposal. Lead author Alex said: "The paper found that terraforming Mars was unfeasible and unlikely to happen any time soon due to the large values of coal being needed to produce a greenhouse effect.
Fresh hint of dark matter seen in neutrino search
Flashes of X-rays from crowded galaxy clusters could be the long-awaited sign that we have found particles of dark matter – the elusive substance thought to make up the bulk of all matter in the universe.
If the results stand up, dark matter would consist of ghostly particles called "sterile" neutrinos. These tantalising particles would be the first kind found beyond the standard set known to science.
Dark matter interacts with ordinary matter via gravity but otherwise scarcely makes itself known. Physicists think its mass could be tied up in an unknown particle. The leading theoretical candidate is a weakly interacting massive particle (WIMP), but our best detectors have yet to yield a confirmed sighting.
Gamma Rays May Be Clue on Dark Matter
A small, newly discovered galaxy orbiting the Milky Way is emitting a surprising amount of electromagnetic radiation in the form of gamma rays, astronomers reported Tuesday. The finding may be the latest in a long string of cosmic false alarms, they said, or it might be that the mysterious dark matter that permeates the universe is finally showing a bit of leg. If confirmed, the results could mean that most of the matter of the universe is in the form of as-yet-unidentified elementary particles, 20 to 100 times as heavy as a proton, that have been drifting and clumping like fog in space ever since the Big Bang.
Nasa finds evidence of a vast ancient ocean on Mars
A massive ancient ocean once covered nearly half of the northern hemisphere of Mars making the planet a more promising place for alien life to have gained a foothold, Nasa scientists say. The huge body of water spread over a fifth of the planet’s surface, as great a portion as the Atlantic covers the Earth, and was a mile deep in places. In total, the ocean held 20 million cubic kilometers of water, or more than is found in the Arctic Ocean, the researchers found.
'Life Not As We Know It': New Research Shows How Exotic Biology May Be Possible on Titan
The search for life elsewhere has long focused on what we are most familiar with on Earth—in other words, “life as we know it,” or organisms which are carbon-based and require water to survive. However, a growing number of scientists are now thinking that alternative forms of life are possible, ones which have never been seen on Earth, but could flourish in other types of alien environments. A new study from Cornell University addresses this very question, demonstrating a form of microscopic life which would be possible on Saturn’s largest moon Titan.
Why isn’t the universe as bright as it should be?
A handful of new stars are born each year in the Milky Way, while many more blink on across the universe. But astronomers have observed that galaxies should be churning out millions more stars, based on the amount of interstellar gas available. Now researchers from MIT, Columbia University, and Michigan State University have pieced together a theory describing how clusters of galaxies may regulate star formation. They describe their framework this week in the journal Nature.
Here’s The First-Ever Photo of Light Behaving as Both a Wave and a Particle
Researchers at the Swiss Federal Institute of Technology in Lausanne in Switzerland have captured the first photograph of light behaving as both a wave and a particle. “This experiment demonstrates that, for the first time ever, we can film quantum mechanics—and its paradoxical nature—directly," Fabrizio Carbone, who led the research team that designed the technique to capture the breakthrough image, said in a statement. "Being able to image and control quantum phenomena at the nanometer scale like this opens up a new route towards quantum computing."
Scientists discover black hole so big it contradicts growth theory
Scientists say they have discovered a black hole so big that it challenges the theory about how they grow. Scientists said this black hole was formed about 900 million years after the Big Bang. But with measurements indicating it is 12 billion times the size of the Sun, the black hole challenges a widely accepted hypothesis of growth rates. "Based on previous research, this is the largest black hole found for that period of time," Dr Fuyan Bian, Research School of Astronomy and Astrophysics, Australian National University (ANU), told Reuters on Wednesday. "Current theory is for a limit to how fast a black hole can grow, but this black hole is too large for that theory." The creation of supermassive black holes remains an open topic of research. However, many scientists have long believed the growth rate of black holes was limited.
The Hills Have Ice... on Mars, That Is
Scientists have been hunting for evidence of water on Mars ever since they started looking at the Red Planet through telescopes. But Mars does have water, and lots of it; solid water in the form of ice locked up in its polar caps and buried under its surface. And, if observations made by ESA’s Mars Express are indicative of similar processes seen on Earth, these ancient hills may also hide hidden deposits of ice.
Did dark matter kill the dinosaurs?
Every so often, the fossil record shows, ecological disasters wipe large numbers of species off the face of Earth. These mass extinctions occur roughly every 26 million to 30 million years—about the same interval at which our solar system passes through the plane of the Milky Way. Putting two and two together, some researchers have proposed that clouds of dust and gas in the galactic plane might disrupt the orbits of far-flung comets and trigger planet-smacking collisions. A new study suggests an additional culprit may lie behind those times of woe: dark matter.
Dark Matter Influences Supermassive Black Hole Growth
Using data from the Sloan Digital Sky Survey and the ROSAT X-ray satellite’s all-sky survey, researchers from the Harvard-Smithsonian Center for Astrophysics detail a distinct relationship between the mass of a dark matter halo and the mass of a black hole.
'Golden stars' pulsate in a strange, non-chaotic way
The first stars known to pulsate in a fractal manner have been discovered by physicists in the US and Germany. According to the researchers, the variable stars may be the first "strange non-chaotic attractors" seen outside the laboratory. The objects were found in data from the Kepler space telescope by looking for stars with two characteristic pulsation frequencies that have a "golden ratio" of approximately 1.62. The discovery could shed light on the physics that drives variable stars and also help astronomers come up with better classification systems for these objects. A variable star dims and brightens as its size and sometimes its shape oscillates at one or more frequencies. Since it was launched in 2009, NASA's Kepler mission has been a boon to astronomers studying variable stars because the telescope has been monitoring the brightness of more than 100,000 stars in its search for distant planets. However, John Learned of the University of Hawaii and Michael Hippke of the Institute for Data Analysis in Neukirchen-Vluyn in Germany noticed the first strange non-chaotic "golden star" when searching the Kepler data for evidence that advanced extraterrestrial civilizations modulate variable stars to communicate between galaxies.
Slimy Microbes May Have Carpeted Earth 3.2 Billion Years Ago
A layer of living scum only a cell thick may have covered parts of Earth more than 3 billion years ago, surviving with the help of nitrogen that these slimy microbes pulled from the atmosphere, a new study finds. This finding suggests that nitrogen may have helped some planets, such as Mars, support life, researchers say.
Although life can exist without oxygen — and did, in the earliest days of life on Earth — without nitrogen, such organisms would be scarce. Nitrogen is needed to create proteins, DNA and RNA, and necessary for plants to grow and photosynthesize. It is an essential nutrient for all life on Earth and must have been available since its origins, researchers said. [7 Theories for the Origin of Life on Earth]
'Shadow biosphere' might be hiding strange life right under our noses
If we came across alien life, would we even know it was alive? That was a central question posed at a session here yesterday at the annual meeting of AAAS (which publishes Science). All known life on Earth fits a particular mold, but life from other planets might break free from that mold, making it difficult for us to identify. We could even be oblivious to unfamiliar forms of life right under our noses. All life as we know it follows a standard protocol, known as the “central dogma,” using DNA and RNA to store genetic information, and translating that into proteins. And all living things rely on the same handful of chemical elements. So, when searching for life in remote or extreme environments scientists typically look for signs of the kind of life we’re familiar with. But, “if we have other organisms out there that do things just slightly differently, we might miss the boat,” geobiologist Victoria Orphan of the California Institute of Technology in Pasadena told attendees.
Cosmic "Reionization" Is More Recent than Predicted
The highly anticipated update of the analysis of data from the European Space Agency's Planck satellite starts with a first paper published in Astronomy and Astrophysics, which already holds in store a few major surprises.
The first article in fact "rejuvenates" the stars of our universe. Thanks to new maps of cosmic background radiation (in particular, those containing "polarization anisotropies" of radiation) scientists have found that the "reionization" process could be more recent than estimated until now.
Evidence for the Presence of Dark Matter in the Innermost Part of the Milky Way
A new study from astrophysicists at Stockholm University provides evidence for the presence of dark matter in the innermost part of the Milky Way, including in our own cosmic neighborhood and the Earth’s location. The study demonstrates that large amounts of dark matter exist around us, and also between us and the Galactic center. The result constitutes a fundamental step forward in the quest for the nature of dark matter.
Dark matter found in Milky Way’s core
Most of the material of the universe is dark matter—stuff we can’t see, though we can still feel its gravity. It was discovered in the 1970s when astronomer Vera Rubin showed that stars in the outer regions of spiral galaxies, far from the center, were moving faster than they should be. This suggested there was some sort of unseen mass in a “halo” around the galaxy. But physicists disagree over whether all this dark matter is at the margin or if there is some in a galaxy’s core. Now, a team of researchers has attempted to answer that question for the Milky Way (pictured). They collected all the data they could find about stellar speeds in the inner regions of our home galaxy to see how they varied with distance from the center, they report online today in Nature Physics. Then they took the best models for how much normal matter there is throughout the galaxy and calculated how fast you would expect stars to be moving if only that normal matter was pulling on them. They found that the measured speeds and calculated speeds didn’t agree, demonstrating that dark matter does indeed play a role in the inner galaxy. The researchers hope their studies will help narrow down searches for the nature of dark matter as well as aid the understanding of galaxy formation.
Planck: Gravitational Waves Remain Elusive
Despite earlier reports of a possible detection, a joint analysis of data from ESA’s Planck satellite and the ground-based BICEP2 and Keck Array experiments has found no conclusive evidence of primordial gravitational waves.
Ancient miniature solar system hints at existence of alien life
A miniature version of solar system with planets like Earth existed 11 billion years ago and could have held ancient life, say scientists.A miniature solar system with five Earth-sized planets existed 11 billion years ago, at the dawn of the universe, scientists have discovered. The planets clustered around a Sun-like star and could point to the existence of life billions of years before the first amoeba existed on our planet. “There are far-reaching implications for this discovery,” said Dr Tiago Campante, from the University of Birmingham's School of Physics and Astronomy, who led the research.
Cosmic 'Nuclear Pasta' May Be Stranger Than Originally Thought
The crusts of neutron stars — cosmic cousins of black holes — possess a weird form of matter known as "nuclear pasta." Now, scientists have found that nuclear pasta may be even stranger than previously thought, forming defects that bond pieces together into complex, disorderly shapes. This complex nuclear pasta could ultimately doom the powerful magnetic fields seen from neutron stars, researchers say.
How the Earth got its nitrogen
Nitrogen may have arrived on Earth in ancient meteorites after the planet had already formed, according to a new study. Reported in the journal Nature Geoscience, the research illustrates how meteorites - often portrayed as portents of doom and destruction - may actually have been key to the development of life on Earth.
Three nearly Earth-size planets found orbiting nearby star
NASA's Kepler Space Telescope, despite being hobbled by the loss of critical guidance systems, has discovered a star with three planets only slightly larger than Earth. The outermost planet orbits in the "Goldilocks" zone, a region where surface temperatures could be moderate enough for liquid water and perhaps life, to exist. The star, EPIC 201367065, is a cool red M-dwarf about half the size and mass of our own sun. At a distance of 150 light years, the star ranks among the top 10 nearest stars known to have transiting planets. The star's proximity means it's bright enough for astronomers to study the planets' atmospheres to determine whether they are like Earth's atmosphere and possibly conducive to life.
How 'Quantum Dots' Could Probe Mysteries of Entanglement
A microwave laser built using tiny particles that act as semiconductors could be used to explore strange phenomena such as quantum entanglement. Researchers at Princeton University used quantum dots — tiny particles of light-emitting nanocrystals that can absorb light from one wavelength and convert it to highly saturated light at specific wavelengths — to build a so-called "maser" that emits light at longer wavelengths than the traditional lasers that we can see. The device could also lead to advances in quantum computing.
Space chemistry could be cooking up icy building blocks of life, study says
Where did the ingredients for life on Earth come from? Many scientists think the basic chemical building blocks for biology were delivered via comet, but the building blocks -- and the building process -- remain a mystery. Now, a team led by French researchers thinks they may have found lab-based evidence that a class of complex organic molecules could have evolved in the ice of star-forming clouds -- and could be a potential source for the organic matter that allowed life on Earth to emerge.
Using a Vanishing Neutron Star to Measure Space-time Warp
In an interstellar race against time, astronomers have measured the space-time warp in the gravity of a binary star and determined the mass of a neutron star--just before it vanished from view.
The international team, including University of British Columbia astronomer Ingrid Stairs, measured the masses of both stars in binary pulsar system J1906. The pulsar spins and emits a lighthouse-like beam of radio waves every 144 milliseconds. It orbits its companion star in a little under four hours. "By precisely tracking the motion of the pulsar, we were able to measure the gravitational interaction between the two highly compact stars with extreme precision," says Stairs, professor of physics and astronomy at UBC.
Did Gravity Save the Universe from 'God Particle' Higgs Boson?
The recently discovered Higgs boson, which helps give particles their mass, could have destroyed the cosmos shortly after it was born, causing the universe to collapse just after the Big Bang. But gravity, the force that keeps planets and stars together, might have kept this from happening, scientists say.
8 Newfound Alien Worlds Could Potentially Support Life
astronomers have discovered eight new exoplanets that may be capable of supporting life as we know it, including what they say are the two most Earthlike alien worlds yet found. All eight newfound alien planets appear to orbit in their parent stars' habitable zone — that just-right range of distances that may allow liquid water to exist on a world's surface — and all of them are relatively small, researchers said.
Planet hunters plot course for habitable worlds
Scott Gaudi is tired of the fighting. An astronomer at Ohio State University in Columbus, he specializes in the notoriously fractious field of exoplanet research, in which battles have included bitter fights over data access and epic rifts between teams searching for planets outside our Solar System. On 4 January in Seattle, Washington, Gaudi will take a tentative first step towards corralling this rowdy bunch. As chair of NASA’s Exoplanet Exploration Program Analysis Group, he will try to nudge a roomful of US exoplanet scientists into generating a coherent, specific vision for where the field should go. The time is right. Researchers have almost finished combing through the thousands of leads that were produced by NASA’s planet-hunting Kepler spacecraft between 2009 and 2013, and are squeezing some more data out of the craft’s limited ‘K2’ mission extension (see Nature 514, 414–415; 2014). By the mid-2020s, budgets permitting, astronomers expect to have a satellite called the Wide-Field Infrared Survey Telescope (WFIRST) busy cataloguing planets that are too far away from their host stars for Kepler to have spotted them. Together, Kepler and WFIRST will produce a rough census of how many planets there are in our Galaxy. But NASA has yet to work out how to tackle the next, more crucial questions: could anything actually live on any of these planets? And what will it take to understand a given world’s chances of being habitable?
The Stellar Origins of Your Toothpaste
It may only take brushing your teeth to help you feel connected to the cosmos. New research suggests that fluorine, an element in toothpaste, may have been forged billions of years ago inside stars that are now long dead. Fluorine is commonly found in products like toothpaste, refrigerants and pharmaceuticals, and it's the 13th most abundant element on Earth. Astronomers already knew that most elements have a stellar origin, but multiple theories speculate on the birth of cosmic fluorine.The new study suggests that red giant stars may be the main creators of fluorine, and the element likely originated in the high pressure cores of these sun-like stars.
The world of physics in 2015
The science story of 2014, which Physics World picked as its Breakthrough of the Year, simply had to be the successful landing of a man-made probe onto a comet, for the first time. Philae dropped on to comet 67P/Churyumov–Gerasimenko in November after a 10-year journey aboard the Rosetta craft – triggering scenes of wild jubilation among scientists and engineers at the European Space Agency (ESA), who had lived through a nail-biting final hour as they waited for radio signals to travel the 511 million kilometres from the comet to Earth after its scheduled landing time. Data from the mission are likely to keep astronomers busy for years to come, including signs that water on Earth came not from comets, as was previously thought, but from asteroids. In fact, 2014 was quite a year for space science, with India putting its Mangalyaan craft in orbit around Mars for the first time and Japan launching the country's second asteroid sample-return mission, Hayabusa 2. Further new findings also came in from the Planck mission, confirming the standard model of cosmology and further constraining what dark matter could be. But what of 2105? What will be the key events in physics and who will have taken the accolades in 12 months' time?
NASA Rover Finds Mysterious Methane Emissions on Mars
Is there life on Mars? The answer may be blowing in the wind. NASA’s Curiosity rover has detected fluctuating traces of methane – a possible sign of life – in the thin, cold air of the Martian atmosphere, researchers announced today at a meeting of the American Geophysical Union. Across Mars and within Gale Crater, where Curiosity is slowly climbing a spire of sedimentary rock called Mount Sharp, the methane exists at a background concentration of slightly less than one part per billion by volume in the atmosphere (ppb). However, for reasons unknown, four times across a period of two months the rover measured much higher methane abundances, at about ten times the background level. Further in-situ studies of the methane emissions could help pin down whether Mars has life, now or in its deep past, though it is unclear when or if those studies will ever take place. The findings are published in the journal Science.
Researchers use real data rather than theory to measure the cosmos
For the first time researchers have measured large distances in the Universe using data, rather than calculations related to general relativity. A research team from Imperial College London and the University of Barcelona has used data from astronomical surveys to measure a standard distance that is central to our understanding of the expansion of the universe. Previously the size of this 'standard ruler' has only been predicted from theoretical models that rely on general relativity to explain gravity at large scales. The new study is the first to measure it using observed data. A standard ruler is an object which consistently has the same physical size so that a comparison of its actual size to its size in the sky will provide a measurement of its distance to earth.
Superconductivity record breaks under pressure
For nearly 30 years, the search for a room-temperature superconductor has focused on exotic materials known as cuprates, which can carry currents without losing energy as heat at temperatures up to 164 Kelvin, or –109 ˚C. But scientists say that they have trumped that record using the common molecule hydrogen sulphide1. When they subjected a tiny sample of that material to pressures close to those inside Earth’s core, the researchers say that it was superconductive at 190 K (–83 ˚C)."If the result is reproduced, it will be quite shocking," says Robert Cava, a solid-state chemist at Princeton University in New Jersey. "It would be a historic discovery."
According to the established theory of superconductivity — dubbed BCS theory after the surnames of its creators, John Bardeen, Leon Cooper and Robert Schrieffer — vibrations in a crystal's atoms can lead electrons to form ‘Cooper pairs’ that can flow through the crystal without resistance. BCS theory was developed in the 1950s, but most physicists believe that it cannot explain superconductivity in cuprates, which was discovered in 1986, or in iron pnictides2, found in 2006.
New Dark Matter Detector Will Be 100 Times More Sensitive to Dark Matter
A team of scientists is building a super sized version of the dark matter detector Lux, called Lux-Zeplin, which will be roughly 100 times more sensitive to dark matter than its predecessor. “What really impressed me was the trip down,” said astrophysicist James Buckley, PhD, speaking of the vertical mile he traveled to get to the site of an underground dark-matter experiment. “You can see you’re moving at a pretty good clip, which, by the way, is three times slower than the cage used to drop when it was a mine. It took us 10 minutes to get down a mile. You just watch the earth flashing by and every once in a while you go past a boarded up tunnel.” The mine is the Homestake Mine, a played-out gold mine in Lead, South Dakota, that has been converted into a warren of underground chambers housing physics experiments that need to be shielded from cosmic radiation.One of these experiments is the Lux detector, designed to detect WIMPs (weakly interacting massive particles). WIMPs are hypothetical subatomic particles thought to make up dark matter in much the same way that electrons and quarks make up ordinary matter. But compared to other particles, WIMPs are elusive and interact only rarely with ordinary matter, and so far Lux hasn’t found any.
Researchers report possible dark matter signal
Researchers with the European Space Agency say they've detected a strange spike in X-rays coming from two cosmic locations -- the Andromeda Galaxy and the Perseus Cluster. The astronomers think the strange emissions could be the signal of dark matter. If confirmed, it would be first direct evidence of dark matter. Astronomers are confident dark matter exists, but it remains purely hypothetical. Still without it, everything scientists know about the universe falls apart -- their calculations for and modeling of various celestial behaviors wouldn't make any sense. It's estimated that as much as 80 percent of the universe is composed of dark matter -- exerting gravitational forces on its surroundings. Because dark matter neither emits nor absorbs light, it's nearly impossible to observe.
Quantum Teleportation Reaches Farthest Distance Yet
A new distance record has been set in the strange world of quantum teleportation. In a recent experiment, the quantum state (the direction it was spinning) of a light particle instantly traveled 15.5 miles (25 kilometers) across an optical fiber, becoming the farthest successful quantum teleportation feat yet. Advances in quantum teleportation could lead to better Internet and communication security, and get scientists closer to developing quantum computers.
Mars Rover Finds Stronger Potential for Life
For lifeless chemical compounds to organize themselves into something alive, scientists generally agree, three sets of things must be present:
â- Standing water and an energy source.
â- Five basic elements: carbon, oxygen, hydrogen, phosphorus and nitrogen.
â- And time, lots of time.
In its search for environments where life might have started on Mars, the Curiosity rover has found the standing water, the energy and the key elements with the right atomic charges. As a result, scientists have concluded that at least some of the planet must have been habitable long ago. But the period when all conditions were right was counted in hundreds to thousands of years, a very small opening by origin-of-life standards.
Continue reading the main story
Some scientists think Gale Crater was once fully buried with sediment and that winds excavated most of it, leaving an 18,000-foot mountain in the middle. (The colors represent different elevations.)Curiosity Rover’s Quest for Clues on MarsDEC. 8, 2014
A painting of early Mars, showing shallow seas across the northern lowlands and weather systems drifting in a denser atmosphere than today's.Looking to Mars to Help Understand Changing ClimatesDEC. 8, 2014
Something to Say About Mars Clockwise from top left: Carl Sagan, President Obama, President Ronald Reagan, Wanda Sykes, Buzz Aldrin, Elon Musk, Orson Welles, Maya Angelou, Neil deGrasse Tyson and Elton John. In the center is a view of a sandstorm on the Martian surface.Mars, ObservedDEC. 8, 2014
First Person: Covering Mars Opened a New WorldDEC. 8, 2014
NASA's Mars rover Curiosity obtained this image using its Left Navigation Camera on the rover's 832 Martian day, called a Sol. Explore Mars for YourselfDEC. 9, 2014
interactive Mars Curiosity Rover TrackerAUG. 5, 2013
That has now changed. John P. Grotzinger of Caltech, the project scientist for the mission, reported at a news conference on Monday that the rover’s yearlong trek to Mount Sharp provided strong new evidence that Gale Crater had large lakes, rivers and deltas, on and off, for millions to tens of millions of years. The geology shows that even when the surface water dried up, plenty of water would have remained underground, he said.
Quantum computer quest
When asked what he likes best about working for Google, physicist John Martinis does not mention the famous massage chairs in the hallways, or the free snacks available just about anywhere at the company's campus in Mountain View, California. Instead, he marvels at Google's tolerance of failure in pursuit of a visionary goal. “If every project they try works,” he says, “they think they aren't trying hard enough.” Martinis reckons that he is going to need that kind of patience. In September, Google recruited him and his 20-member research team from the University of California, Santa Barbara, and set them to work on the notoriously difficult task of building quantum computers: devices that exploit the quirks of the quantum world to carry out calculations that ordinary computers could not finish in the lifetime of the Universe.
See it, touch it, feel it: Team develops invisible 3-D haptic shape
Technology has changed rapidly over the last few years with touch feedback, known as haptics, being used in entertainment, rehabilitation and even surgical training. New research, using ultrasound, has developed an invisible 3-D haptic shape that can be seen and felt. The research paper, published in the current issue of ACM Transactions on Graphics and which will be presented at this week's SIGGRAPH Asia 2014 conference [3-6 December], demonstrates how a method has been created to produce 3D shapes that can be felt in mid-air. The research, led by Dr Ben Long and colleagues Professor Sriram Subramanian, Sue Ann Seah and Tom Carter from the University of Bristol's Department of Computer Science, could change the way 3D shapes are used. The new technology could enable surgeons to explore a CT scan by enabling them to feel a disease, such as a tumour, using haptic feedback.
The method uses ultrasound, which is focussed onto hands above the device and that can be felt. By focussing complex patterns of ultrasound, the air disturbances can be seen as floating 3D shapes. Visually, the researchers have demonstrated the ultrasound patterns by directing the device at a thin layer of oil so that the depressions in the surface can be seen as spots when lit by a lamp. The system generates an invisible 3D shape that can be added to 3D displays to create something that can be seen and felt. The research team have also shown that users can match a picture of a 3D shape to the shape created by the system.
European probe shoots down dark-matter claims
The first full analysis of the data gathered by the European Space Agency’s Planck spacecraft has resolved some conundrums raised by earlier cosmology studies — but has made the riddle of dark matter more obscure. The Planck team did not yet address a controversy over the gravitational waves from the Big Bang announced in March, but plans to do so in an upcoming study.The space observatory has produced the most detailed full-sky survey yet of the cosmic microwave background (CMB), radiation left over from the explosive birth of the Universe some 13.8 billion years ago. The maps are based on all four years of Planck observations, from launch in 2009 to decommissioning in 2013, and include both the temperature and the polarization of the CMB.
Gravity may have saved the universe after the Big Bang
New research by a team of European physicists could explain why the universe did not collapse immediately after the Big Bang. Studies of the Higgs particle - discovered at CERN in 2012 and responsible for giving mass to all particles - have suggested that the production of Higgs particles during the accelerating expansion of the very early universe (inflation) should have led to instability and collapse.
How to estimate the magnetic field of an exoplanet
Scientists developed a new method which allows to estimate the magnetic field of a distant exoplanet, i.e., a planet, which is located outside the Solar system and orbits a different star. Moreover, they managed to estimate the value of the magnetic moment of the planet HD 209458b.
Parallel Worlds Could Explain Wacky Quantum Physics
The idea that an infinite number of parallel worlds could exist alongside our own is hard to wrap the mind around, but a version of this so-called Many Worlds theory could provide an answer to the controversial idea of quantum mechanics and its many different interpretations. Bill Poirier, a professor of physics at Texas Tech University in Lubbock, proposed a theory that not only assumes parallel worlds exist, but also says their interaction can explain all the quantum mechanics "weirdness" in the observable universe.
GPS satellites might be able to detect elusive dark matter
The everyday use of a GPS device might be to find your way around town or even navigate a hiking trail, but for two physicists, the Global Positioning System might be a tool in directly detecting and measuring dark matter, so far an elusive but ubiquitous form of matter responsible for the formation of galaxies.
Andrei Derevianko, of the University of Nevada, Reno, and his colleague Maxim Pospelov, of the University of Victoria and the Perimeter Institute for Theoretical Physics in Canada, have proposed a method for a dark-matter search with GPS satellites and other atomic clock networks that compares times from the clocks and looks for discrepancies.
Frigid matter powers first quantum circuits
Move over, electrons – circuits could one day be powered by frigid quantum matter. Ultra-cold clouds of atoms called Bose-Einstein condensates act as a single quantum object, and the goal has been to build "atomtronic" circuits with them. But the condensate's delicate quantum state can easily fall apart. Now Changhyun Ryu and Malcolm Boshier of the Los Alamos National Laboratory in New Mexico have found a way to do it. Their circuits are built from two laser beams, one that creates a horizontal sheet of light to act as a circuit board, and another vertical laser that traces out the path of the circuit. The condensate, which is made from around 4000 cooled rubidium atoms, is trapped inside the beams by the same forces used to create optical tweezers, which can manipulate particles on a small scale. The condensate is set in motion by creating a slightly sloped path. The team ran the condensate along straight lines, in a circle and through a Y junction – all essential components of a circuit. Since the circuits are just made from light, they can be reconfigured as the atoms are moving, letting you squeeze a complex circuit into a small space, says Boshier.
Dark Matter's New Wrinkle: It May Behave Like Wavy Fluid
The mysterious dark matter that makes up most of the matter in the universe may behave more like wavy fluids than solid particles, helping to explain the shapes of galaxies, a new study suggests. Dark matter is one of the greatest mysteries in the cosmos. It is thought to be an invisible and mostly intangible substance that makes up five-sixths of all matter in the universe. The scientific consensus is that dark matter is composed of a new type of particle, one that interacts very weakly with all the known forces of the universe and is mostly only detectable via the gravitational pull it exerts. However, what kind of particle dark matter consists of remains unknown.
Dark Matter Black Holes Could Be Destroying Stars at the Milky Way’s Center
Dark matter may have turned spinning stars into black holes near the center of our galaxy, researchers say. There, scientists expected to see plenty of the dense, rotating stars called pulsars, which are fairly common throughout the Milky Way. Despite numerous searches, however, only one has been found, giving rise to the so-called “missing pulsar problem.” A possible explanation, according to a new study, is that dark matter has built up inside these stars, causing the pulsars to collapse into black holes. (These black holes would be smaller than the supermassive black hole that is thought to lurk at the very heart of the galaxy.)
Why a Physics Revolution Might Be on Its Way
European satellite could discover thousands of planets in Earth's galaxy
A recently launched European satellite could reveal tens of thousands of new planets within the next few years, and provide scientists with a far better understanding of the number, variety and distribution of planets in our galaxy, according to research published today.Researchers from Princeton University and Lund University in Sweden calculated that the observational satellite Gaia could detect as many as 21,000 exoplanets, or planets outside of Earth's solar system, during its five-year mission. If extended to 10 years, Gaia could detect as many as 70,000 exoplanets, the researchers report. The researchers' assessment is accepted in the Astrophysical Journal and was published Nov. 6 in advance-of-print on arXiv, a preprint database run by Cornell University.
String field theory could be the foundation of quantum mechanics
Two USC researchers have proposed a link between string field theory and quantum mechanics that could open the door to using string field theory — or a broader version of it, called M-theory — as the basis of all physics. This could solve the mystery of where quantum mechanics comes from,” said Itzhak Bars, USC Dornsife College of Letters, Arts and Sciences professor and lead author of the paper.
Bars collaborated with Dmitry Rychkov, his Ph.D. student at USC. The paper was published online on Oct. 27 by the journal Physics Letters.
Rather than use quantum mechanics to validate string field theory, the researchers worked backwards and used string field theory to try to validate quantum mechanics.
In their paper, which reformulated string field theory in a clearer language, Bars and Rychov showed that a set of fundamental quantum mechanical principles known as “commutation rules’’ that may be derived from the geometry of strings joining and splitting. “Our argument can be presented in bare bones in a hugely simplified mathematical structure,” Bars said. “The essential ingredient is the assumption that all matter is made up of strings and that the only possible interaction is joining/splitting as specified in their version of string field theory.”
New Experiment Aims to Crack Neutrino Mass Mystery
Neutrinos are everywhere in the universe, but we cannot see them or feel them and can almost never stop them. They stream through our bodies by the trillions every second, flitting through the spaces between our atoms with nary a collision. These ghostly particles were created in abundance during the big bang, and stars like the sun pump out more all the time. Yet for all their plentitude, neutrinos may be the most mysterious particles in the cosmos.
For decades physicists thought neutrinos weighed nothing, and they were shocked in 1998 to discover that the particles do have very small, but nonzero, masses. Exactly how much mass they have is still unknown. The larger question, however, is why they have mass at all.
The unexpected mass of neutrinos represents a deviation from the reigning laws of particle physics, called the Standard Model, so teasing out the reason for this mass could lead the way to a deeper and fuller explanation of the particles that make up our world. “It’s really the first crack in the Standard Model in quite some time,” says Indiana University physicist Mark Messier, “and there’s a lot of interest to try to pull that crack open and see what’s going on there.” Furthermore, neutrinos seem to be at the heart of a larger mystery: the question of why we live in a universe made of matter and not antimatter. The two types of stuff should have been created in roughly equal measures at the beginning of time, but somehow matter won out. Scientists suspect that solving the neutrino mass problem may help reveal why that is.
Universe may face a darker future
New research offers a novel insight into the nature of dark matter and dark energy and what the future of our Universe might be. Researchers in Portsmouth and Rome have found hints that dark matter, the cosmic scaffolding on which our Universe is built, is being slowly erased, swallowed up by dark energy. The findings appear in the journal Physical Review Letters, published by the American Physical Society. In the journal cosmologists at the Universities of Portsmouth and Rome, argue that the latest astronomical data favours a dark energy that grows as it interacts with dark matter, and this appears to be slowing the growth of structure in the cosmos.
Ultracold disappearing act: 'Matter waves' move through one another but never share space
A disappearing act was the last thing Rice University physicist Randy Hulet expected to see in his ultracold atomic experiments, but that is what he and his students produced by colliding pairs of Bose Einstein condensates (BECs) that were prepared in special states called solitons. Hulet's team documented the strange phenomenon in a new study published online this week in the journal Nature Physics.
Evidence Builds for Dark Matter Explosions at the Milky Way’s Core
So far, dark matter has evaded scientists’ best attempts to find it. Astronomers know the invisible stuff dominates our universe and tugs gravitationally on regular matter, but they do not know what it is made of. Since 2009, however, suspicious gamma-ray light radiating from the Milky Way’s core—where dark matter is thought to be especially dense—has intrigued researchers. Some wonder if the rays might have been emitted in explosions caused by colliding particles of dark matter. Now a new gamma-ray signal, in combination with those already detected, offers further evidence that this might be the case.
Can the wave function of an electron be divided and trapped?
Electrons are elementary particles — indivisible, unbreakable. But new research suggests the electron's quantum state — the electron wave function — can be separated into many parts. That has some strange implications for the theory of quantum mechanics.
Chilly Record! Coldest Object on Earth Created in Lab
chunk of copper became the coldest cubic meter (35.3 cubic feet) on Earth when researchers chilled it to 6 millikelvins, or six-thousandths of a degree above absolute zero (0 Kelvin). This is the closest a substance of this mass and volume has ever come to absolute zero. Researchers put the 880-lb. (400 kilograms) copper cube inside a container called a cryostat that is specially designed to keep items extremely cold. This is the first cryostat built that is capable of keeping substances so close to absolute zero.
Astronomers Capture First-Ever Image Of A Nova’s Exploding Fireball Stage
Observations of the expanding thermonuclear fireball from a nova that erupted last year have resulted in the first ever images of an exploding star during this stage and revealed how the ejected material’s structure evolves as the gas cools and expands, researchers from Georgia State University reported on Sunday. The observations, which were conducted by researchers working at GSU’s Center for High Angular Resolution Astronomy (CHARA), reveal that the expansion is more complex than previous models had predicted. Lead author Gail Schaefer, an astronomer working at Georgia State, and 37 colleagues representing 17 institutions report their findings in the latest edition of the journal Nature.
A quantum world arising from many ordinary ones
The bizarre behaviour of the quantum world — with objects existing in two places simultaneously and light behaving as either waves or particles — could result from interactions between many 'parallel' everyday worlds, a new theory suggests. “It is a fundamental shift from previous quantum interpretations,” says Howard Wiseman, a theoretical quantum physicist at Griffith University in Brisbane, Australia, who together with his colleagues describes the idea in Physical Review X.
Historic quantum software is run for the first time
The first piece of software to show the potential of quantum computing has finally been run on a real machine, 20 years after it was initially dreamed up. Although it doesn't do anything useful on its own, implementing the algorithm could lead to more practical computers powered by the strange properties of quantum mechanics. Quantum computers should be much faster than ordinary ones, but only at tasks for which there is a quantum algorithm – software that takes advantage of the computer's quantum nature. Without these algorithms, quantum computers are just regular computers that are much harder to build. One of the best-known pieces of quantum software is Shor's algorithm, which factorises large numbers into their prime components – a notoriously slow and difficult problem to solve classically. Shor's algorithm has been run in a limited way using photons sent through the air and on silicon chips – but a full-blown quantum computer capable of running it could threaten online encryption, which relies on large primes.
3-D map of the adolescent universe
Using extremely faint light from galaxies 10.8-billion light years away, scientists have created one of the most complete, three-dimensional maps of a slice of the adolescent universe. The map shows a web of hydrogen gas that varies from low to high density at a time when the universe was made of a fraction of the dark matter we see.
Physicists see potential dark matter from the Sun
An analysis of 12 years’ worth of telescope data has found a signal that some physicists think could be the first detection of dark matter1. Astronomers have found variations in the stream of X-rays seen by a European Space Agency observatory that matches what would be expected if axions — a hypothetical dark-matter particle — were interacting with Earth’s magnetic field. Dark matter is the name given to the substance thought to make up some 85% of all the matter in the Universe. It is ‘dark’ because its presence can be inferred from the pull it exerts on stars in the Universe, but it has evaded all attempts so far to detect it convincingly. If confirmed, the axion finding would be a huge discovery. The study leader, astronomer George Fraser of the University of Leicester, UK, died just two days after he and his co-authors submitted the paper for publication. The study was Fraser’s “most astonishing swan song”, wrote Andy Lawrence, an astronomer at the Institute for Astronomy in Edinburgh, UK, in his blog the e-Astronomer.
Physicists build reversible laser tractor beam
Laser physicists have built a tractor beam that can repel and attract objects, using a hollow laser beam that is bright around the edges and dark in its centre.
It is the first long-distance optical tractor beam and moved particles one fifth of a millimetre in diameter a distance of up to 20 centimetres, around 100 times further than previous experiments.
Desktop sonic black hole emits Hawking radiation
A model black hole that traps sound instead of light has been caught emitting quantum particles, thought to be the analogue of the theoretical Hawking radiation. The effect may be the first time that a lab-based black hole has created Hawking particles in the same way expected from real black holes.
Two new strange and charming particles appear at LHC
Two new particles have been discovered by the LHCb experiment at CERN's Large Hadron Collider near Geneva, Switzerland. One of them has a combination of properties that has never been observed before. The particles, named DS3*(2860)– and DS1*(2860)–, are about three times as massive as protons. Physicists analysed LHCb observations of an energy peak that had been spotted in 2006 by the BaBar experiment at Stanford University in California, but whose cause was still unknown.
Texas border town to become next Cape Canaveral
New Particle Is Both Matter and Antimatter
Researchers see signature of “Majorana particles” inside superconducting iron.
Since the 1930s scientists have been searching for particles that are simultaneously matter and antimatter. Now physicists have found strong evidence for one such entity inside a superconducting material. The discovery could represent the first so-called Majorana particle, and may help researchers encode information for quantum computers.
Physicists think that every particle of matter has an antimatter counterpart with equal mass but opposite charge. When matter meets its antimatter equivalent, the two annihilate one another. But some particles might be their own antimatter partners, according to a 1937 prediction by Italian physicist Ettore Majorana. For the first time researchers say they have imaged one of these Majorana particles, and report their findings in the October 3 Science.
Deep Space, Branching Molecules, and Life’s Origins?
If biologically important organic molecules like amino acids could form in interstellar space, the implications would be enormous. On the Earth we find plenty of amino acid species inside certain types of meteorites, so at a minimum these compounds can form during the assembly of a proto-stellar, proto-planetary system (at least this one) and end up intact on the surface of rocky planets. The implication is that there may be a ‘starter-mix’ of pre-biotic chemistry for young planets that comes from off-world, and which could play a role in the origins of life.
Quantum bits get their first compression
Without algorithms that compress data to encode information into fewer bits, hard drives would clog up and Internet traffic would slow to a snail's pace. Now, a group of physicists in Canada has shown for the first time that it is possible to compress the kind of data that might be used in the computers of tomorrow — known as quantum bits, or qubits.
Quantum computers promise to perform certain tasks, such as cracking encryption keys or searching databases, exponentially faster than conventional computers can. Such pace is possible in part because while in a classical computer a bit of information can be either a 0 or a 1, a quantum computer can store the information as both values simultaneously, so that qubits can exist in a wide range of 'superpositions' of the two states.
Higgs Boson to the World Wide Web: 7 Big Discoveries Made at CERN
The world's biggest atom smasher, where monumental discoveries such as the detection of the once-elusive Higgs boson particle and the creation of antimatter have occurred, is celebrating its 60th anniversary today (Sept. 29).
Founded in 1954, the European Organization for Nuclear Research, or CERN, located near Geneva on the French-Swiss border, contains some of the largest and most advanced particle accelerators in the world. In honor of the lab's anniversary, here are a few of the greatest discoveries made at CERN over the past six decades.
'Space Bubbles' May Have Doomed Key Afghan War Mission
Twelve years ago, a U.S. military rescue mission in Afghanistan went horribly wrong. A Chinook helicopter carrying U.S. troops failed to receive a crucial radio message and was shot down over the snow-covered peak of Takur Ghar.
But the radio failure was not caused by malfunctioning equipment. Instead, a giant, 62-mile-long (100 kilometers) "plasma bubble" made up of clouds of electrically charged particles was responsible for the communication blackout, new research suggests.
Is Our Universe Really 'Slip Slidin Away'?
Ok. Some corners of the news media have headlined a comment made by Stephen Hawkings about Hawkings says Higgs Boson could destroy the universe. To their credit, the stories you read are presented tongue-in-cheek with the disclaimer that it is really unlikely that this will happen. But if it does, our familiar universe will simply wink-out and be replaced by another kind of universe based upon different laws. Presumably the transition will be instantaneous and you will not feel a thing.
Quantum Entanglement Creates New State of Matter
Half a million ultracold atoms were linked together in the first-ever “macroscopic spin singlet” state.Physicists have used a quantum connection Albert Einstein called “spooky action at a distance” to link 500,000 atoms together so that their fates were entwined. The atoms were connected via “entanglement,” which means an action performed on one atom will reverberate on any atom entangled with it, even if the particles are far apart. The huge cloud of entangled atoms is the first “macroscopic spin singlet,” a new state of matter that was predicted but never before realized.
Entanglement is a consequence of the strange probabilistic rules of quantum mechanics and seems to permit an eerie instantaneous connection over long distances that defies the laws of our macroscopic world (hence Einstein’s “spooky” remark). A spin singlet is one form of entanglement where multiple particles’ spins—their intrinsic angular momentum—add up to 0, meaning the system has zero total angular momentum.
Photons weave their way through a triple slit
A flaw in how quantum-interference experiments are interpreted has been quantified for the first time by a team of physicists in India. Using the "path integral" formulation of quantum mechanics, the team calculated the interference pattern created when electrons or photons travel through a set of three slits. It found that non-classical paths – in which a particle can weave its way through several slits – must be considered along with the conventional quantum superposition of three direct paths (one through each of the slits). The team says the effect should be measurable in experiments involving microwave photons, and that the work could also provide insights into potential sources of decoherence in some quantum-information systems.
Quantum teleportation from a telecom-wavelength photon to a solid-state quantum memory
Quantum teleportation1 is a cornerstone of quantum information science due to its essential role in important tasks such as the long-distance transmission of quantum information using quantum repeaters2, 3. This requires the efficient distribution of entanglement between remote nodes of a network4. Here, we demonstrate quantum teleportation of the polarization state of a telecom-wavelength photon onto the state of a solid-state quantum memory. Entanglement is established between a rare-earth-ion-doped crystal storing a single photon that is polarization-entangled with a flying telecom-wavelength photon5, 6. The latter is jointly measured with another flying polarization qubit to be teleported, which heralds the teleportation. The fidelity of the qubit retrieved from the memory is shown to be greater than the maximum fidelity achievable without entanglement, even when the combined distances travelled by the two flying qubits is 25â...km of standard optical fibre. Our results demonstrate the possibility of long-distance quantum networks with solid-state resources.
Cosmic inflation: BICEP 'underestimated' dust problem
One of the biggest scientific claims of the year has received another set-back. In March, the US BICEP team said it had found a pattern on the sky left by the rapid expansion of space just fractions of a second after the Big Bang. The astonishing assertion was countered quickly by others who thought the group may have underestimated the confounding effects of dust in our own galaxy. That explanation has now been boosted by a new analysis from the European Space Agency's (Esa) Planck satellite. In a paper published on the arXiv pre-print server, Planck's researchers find that the part of the sky being observed by the BICEP team contained significantly more dust than it had assumed. This new information does not mean the original claim is now dead. Not immediately, anyway.
Milky Way may bear 100 million life-giving planets
There are some 100 million other places in the Milky Way galaxy that could support complex life, report a group of university astronomers in the journal Challenges. They have developed a new computation method to examine data from planets orbiting other stars in the universe. Their study provides the first quantitative estimate of the number of worlds in our galaxy that could harbor life above the microbial level.
Synopsis: More Dark Matter Hints from Cosmic Rays?
Excitement still surrounds a possible hint of dark matter in an unexpected excess of cosmic-ray antielectrons (positrons) relative to electrons. A new set of data from the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station confirms the positron excess and provides the most accurate measurement to date of the shape of both the electron and positron spectra. The analysis reveals that the positron flux is significantly different from the electron flux above 30 GeV in energy, which suggests that positrons and electrons have a different origin.
Cosmic rays are predominantly protons and other nuclei, but electrons and positrons make up part of the mix. Standard astrophysical models of interstellar particle collisions predict that, in cosmic rays, the fraction of positrons relative to electrons should decrease with energy. However, recent observations from satellites (e.g., PAMELA and Fermi) and from AMS have shown that the positron fraction actually increases with energy.
The AMS experiment, which has a large permanent magnet that allows particle discrimination, has been collecting data since May 2011. Out of 41 billion detection events, the AMS collaboration has identified 580,000 positrons and 9.2 million electrons (50% more than in their previous data release, see 3 April 2013 Viewpoint). Thanks to the additional data, they were able to extend their measurements of the positron flux up to 500 GeV and, similarly, of the electron flux up to 700 GeV. The high-precision data reveal that both spectra change their slope at around 30 GeV but behave differently towards higher energies: the positron flux drops off much more slowly than the electron flux. One possible explanation for this spectral difference is that the positrons are being created in annihilations of dark matter particles. The authors say data at higher energy will be needed to confirm a dark matter origin.
This research is published in Physical Review Letters.
Surprise! Monster Black Hole Found in Dwarf Galaxy
Astronomers have just discovered the smallest known galaxy that harbors a huge, supermassive black hole at its core. The relatively nearby dwarf galaxy may house a supermassive black hole at its heart equal in mass to about 21 million suns. The discovery suggests that supermassive black holes may be far more common than previously thought.
Stalking the Shadow Universe
For centuries people have found meaning — or thought they did — in what they could see in the sky, the shapes of the constellations echoing old myths, the sudden feathery intrusion of comets, the regular dances of the planets, the chains of galaxies, spanning unfathomable distances of time and space.
Since the 1980s, however, astronomers have been forced to confront the possibility that most of the universe is invisible, and that all the glittering chains of galaxies are no more substantial, no more reliable guides to physical reality, than greasepaint on the face of a clown.
The brute mathematical truth is that atoms, the stuff of stars, you and me, make up only 5 percent of the universe by weight. A quarter of it is made of mysterious particles known as dark matter, and the remaining 70 percent a mysterious form of energy called dark energy. Physicists theorize that dark matter could be exotic particles left over from the Big Bang. They don’t know what it is, but they can deduce that dark matter is there by its gravitational effect on the things they can see. If Newton’s laws of gravity held over cosmic distances, huge amounts of more matter than we can see were needed to provide the gravitational glue to keep clusters of galaxies from flying apart, and to keep the stars swirling around in galaxies at high speed.
Scattered neutrons could mimic DAMA-LIBRA's 'dark matter' modulation
For the last 16 years, researchers at the DAMA/LIBRA experiment in Italy have seen a controversial annual oscillation in the signal from their dark-matter detector. This type of variation would be seen if the Milky Way galaxy was wreathed in a "halo" of dark matter. But apart from the CoGENT dark-matter experiment in the US, no other dark-matter searches have seen a similar effect. Now, a physicist at Durham University in the UK has proposed an alternative source for the modulation in the form of neutrons, which are knocked out of atoms by muons and neutrinos scattering in the rock or shielding material around DAMA/LIBRA.
Stalking the Shadow Universe
For centuries people have found meaning — or thought they did — in what they could see in the sky, the shapes of the constellations echoing old myths, the sudden feathery intrusion of comets, the regular dances of the planets, the chains of galaxies, spanning unfathomable distances of time and space.
Since the 1980s, however, astronomers have been forced to confront the possibility that most of the universe is invisible, and that all the glittering chains of galaxies are no more substantial, no more reliable guides to physical reality, than greasepaint on the face of a clown.
Universe Shouldn't Be Here, According to Higgs Physics
The universe shouldn't exist — at least according to a new theory. Modeling of conditions soon after the Big Bang suggests the universe should have collapsed just microseconds after its explosive birth, the new study suggests.
Nearby Alien Planet May Be Capable of Supporting Life
A newfound alien world might be able to support life — and it's just a stone's throw from Earth in the cosmic scheme of things. An international team of astronomers has discovered an exoplanet in the star Gliese 832's "habitable zone" — the just-right range of distances that could allow liquid water to exist on a world's surface. The planet, known as Gliese 832c, lies just 16 light-years from Earth. (For perspective, the Milky Way galaxy is about 100,000 light-years wide; the closest star to Earth, Proxima Centauri, is 4.2 light-years away.)
The First Indirect Detection of Dark Matter
Dark matter is one of the universe's most befuddling, and elusive, components. It could make up roughly a quarter of the universe's total mass and energy, yet no one knows for sure because no one has actually seen it. Well, it may be showing itself at last. nasa's Fermi Gamma-ray Space Telescope has recorded high-energy gamma-ray light emanating from the center of the Milky Way that fits well with dark matter predictions. “I would consider it currently the most exciting signal that we have,” said physicist Rafael Lang of Purdue University, who was not involved in the study, at the American Physical Society's meeting in April in Savannah, Ga. If the light were truly caused by dark matter, it would be the first indirect detection of the particles that make up this shadowy substance.
Higgs Boson Confirms Reigning Physics Model Yet Again
For a subatomic particle that remained hidden for nearly 50 years, the Higgs boson is turning out to be remarkably well behaved. Yet more evidence from the world's largest particle accelerator, the Large Hadron Collider (LHC) in Switzerland, confirms that the Higgs boson particle, thought to explain why other particles have mass, acts just as predicted by the Standard Model, the dominant physics theory that describes the menagerie of subatomic particles that make up the universe.
Dark Matter Mystery Deepens
New results from the particle detector attached outside the International Space Station show something else beside ordinary matter is generating cosmic rays, the lead researcher said Tuesday.
Gravitational-wave team admits findings could amount to dust
Astronomers who announced in March that they had evidence of waves originating from the Big Bang have adopted a more cautious stance as they publish their results in a peer-reviewed journal — just as new independent data cast additional doubt on the original findings. Settlement for UCLA chemist over student death China rover scans deep into the Moon's geological history BICEP2 team concedes problems with gravitational- wave signal
In a paper published on 19 June in Physical Review Letters1, the BICEP2 collaboration, named after the South Pole telescope they used to look at a patch of the microwave sky, acknowledges that the foreground effect of dust in the Milky Way may account for a larger fraction than previously estimated — and possibly all — of what had appeared to be a signal from the dawn of time.
Plasmonic waveguide stops light in its tracks
A simple, solid-state waveguide that can "stop" light has been proposed by physicists in the UK. The researchers say that their device – which has yet to be built in the lab – would be straightforward to create and could be used as an interface between electronic and optical circuits. The waveguide could also lead to the development of new lasers and molecular-imaging systems.
Large Hadron Collider Discovers 'Very Exotic Matter' That Challenges Traditional Physics
Scientists have discovered a new "very exotic" type of matter that challenges the traditional model of particle physics. Using the Large Hadron Collider beauty (LHCb) Collaboration at Cern in Geneva, the New York scientists say they have confirmed the discovery of exotic hadrons which cannot be classified using the traditional quark model – a classification scheme for hadrons.
Physicists link neutron stars to earthbound alloys
Neutron stars could share some unlikely similarities with metallic alloys here on Earth. That's the conclusion of two physicists in Scandinavia, who have carried out calculations that reveal that the nuclei and neutrons in the outer crust of these stars play a similar role to the different metals in an alloy. The finding could provide insights into some observable properties of neutron stars, including gamma-ray bursts, rotational glitches and gravitational waves.
New material offers angular control over light
A new material that filters light according to its direction of travel has been developed by physicists in the US and China. Made of alternating layers of two different transparent materials, the structure is just 8 μm thick and offers a new and extremely simple way of controlling the direction in which light propagates. According to its inventors, the material could be used in a range of applications, from photography to solar energy.
Lasers to Solve the Black Hole Information Paradox?
In an effort to help solve the black hole information paradox that has immersed theoretical physics in an ocean of soul searching for the past two years, two researchers have thrown their hats into the ring with a novel solution: Lasers.
Big Bang Discovery Opens Doors to the "Multiverse"
Bored with your old dimensions—up and down, right and left, and back and forth? So tiresome. Take heart, folks. The latest news from Big Bang cosmologists offers us some relief from our humdrum four-dimensional universe. Gravitational waves rippling through the aftermath of the cosmic fireball, physicists suggest, point to us inhabiting a multiverse, a universe filled with many universes.
Big Bang breakthrough announced; gravitational waves detected
There's no way for us to know exactly what happened some 13.8 billion years ago, when our universe burst onto the scene. But scientists announced Monday a breakthrough in understanding how our world as we know it came to be.
If the discovery holds up to scrutiny, it's evidence of how the universe rapidly expanded less than a trillionth of a second after the Big Bang
Paradox Solved? How Information Can Escape from a Black Hole
Every black hole conceals a secret — the quantum remains of the star from which it formed, say a group of scientists, who also predict that these stars can later emerge once the black hole evaporates. The researchers call these objects "Planck stars" and believe that they could solve a very important question in modern physics: the information paradox, or the question of what happens to information contained in matter that falls into a black hole. The idea could also finally reconcile quantum mechanics and Albert Einstein’s general theory of relativity that describes gravity, thus showing how a theory of quantum gravity might solve longstanding puzzles in the world of physics.
Weird 'Entangled' Light Gives Microscope Sharper Images
The first microscope that uses the eerie trick of quantum entanglement to increase its sensitivity has been developed by Japanese researchers. The new tool relies on a weird principle of quantum mechanics, in which two particles can become entangled so that even when separated by large distances, say light-years, they are intimately connected. Using such entangled photons, or particles of light, the microscope reveals things that are completely transparent, visualizing them in a much better quality than could be done with ordinary light.
Population of Known Alien Planets Nearly Doubles as NASA Discovers 715 New Worlds
NASA's Kepler space telescope has discovered more than 700 new exoplanets, nearly doubling the current number of confirmed alien worlds. The 715 newfound planets, which scientists announced today (Feb. 26), boost the total alien-world tally to between 1,500 and 1,800, depending on which of the five main extrasolar planet discovery catalogs is used. The Kepler mission is responsible for more than half of these finds, hauling in 961 exoplanets to date, with thousands more candidates awaiting confirmation by follow-up investigations.