Cool your jets: NASA's quantum spaceship is doubtful - space - 06 August 2014 - New Scientist

Cool your jets: NASA's quantum spaceship is doubtful - space - 06 August 2014 - New Scientist: ...as Baez points out, this new device in question wasn't even tested in a vacuum! That's extremely important; assuming the measurements are real, the thrust seen could be due to air being warmed up and moving around.

First Evidence Of A Correction To The Speed of Light — The Physics arXiv Blog — Medium

First Evidence Of A Correction To The Speed of Light — The Physics arXiv Blog — Medium: Because all previous speed-of-light calculations have relied only on general relativity, they do not take into account the tiny effects of quantum mechanics. But these effects are significant over such long distances and through such a large mass as the Milky Way, says Franson...

Franson’s idea is that the gravitational potential must influence the electron-positron pair because they have mass. “Roughly speaking, the gravitational potential changes the energy of a virtual electron-positron pair, which in turn produces a small change in the energy of a photon,” he says. “This results in a small correction to the angular frequency of a photon and thus its velocity.”

Oddball space neutrinos may be spawn of dark matter - physics-math - 15 August 2013 - New Scientist

Oddball space neutrinos may be spawn of dark matter - physics-math - 15 August 2013 - New Scientist: ...apart from those seen after a 1987 supernova explosion, none had been detected from beyond the solar system...

Then, earlier this year, the IceCube collaboration...reported two deep-space neutrinos...

...expected sources of such neutrinos... should also produce neutrinos of energies different from those seen by IceCube so far...

They calculate that heavyweight dark matter particles of about 1 PeV would decay either directly into neutrinos of about 1 PeV, or into other particles and then into neutrinos with energies of tens of TeV. "It exactly reproduces the features that you see in IceCube," says Serpico...

Neutrino shape-shift points to new physics - physics-math - 20 July 2013 - New Scientist

Neutrino shape-shift points to new physics - most experiments measure the rate of neutrino oscillation by starting with one neutrino type and seeing how many of them disappear by the time the particles reach a detector, rather than seeing the transformed neutrino arrive anywhere...
They have detected a total of 28 electron neutrinos, when fewer than 5 would be expected if the neutrinos were not oscillating. Odds that the result is a fluke are less than one in a trillion...
Now that we have seen the muon neutrino morph into the electron neutrino in normal matter, physicists can run the T2K experiment with a beam of anti-muon neutrinos. Subtle differences in the way neutrinos and antineutrinos oscillate could have skewed the ratios of matter and antimatter production in the early universe...

Twist in dark matter tale hints at shadow Milky Way

Twist in dark matter tale hints at shadow Milky Way: In 2008, when the PAMELA satellite found a similar excess of positrons, Neal Weiner of New York University and colleagues suggested that WIMPs are drawn together under a force of their own...

Observations of the orbits of stars around galaxies suggest that all galaxies, including the Milky Way, are surrounded by a spherical cloud of dark matter (see diagram). But if a fraction of dark matter particles interact with each other, they would combine into atom-like structures and eventually collapse into a spinning disc. This is how ordinary matter formed the Milky Way. The resulting shadow Milky Way could be spinning right along with the visible one, or it could end up tilted at a slight angle, she adds.

Planck shows almost perfect cosmos – plus axis of evil

Planck shows almost perfect cosmos – plus axis of evil: "The overall conclusion is that standard cosmology is an extremely good match to Planck data," said Efstathiou. "If I were an inflationary theorist I would be extremely happy."

...Planck reveals that one half of the universe has bigger variations than the other. Planck's detectors are over 10 times more sensitive and have about 2.5 times the angular resolution of WMAP's, giving cosmologists a much better look at this alignment. "We can be extremely confident that these anomalies are not caused by galactic emissions and not caused by instrumental effects..."

Researchers at SLAC find too many taus decay from bottom quarks to fit Standard Model

Researchers at SLAC find too many taus decay from bottom quarks to fit Standard Model: Instead of the 20% frequency rate predicted for D mesons, the researchers found a 31% rate (and a 25% rate for D* mesons instead of the predicted 23%)...

To explain the differences between the theories and observed results the researchers suggest that perhaps another Higgs Boson is at work; SUSY suggests there may be as many as four, though research at CERN is still ongoing to prove that what was observed earlier this year was in fact an actual Higgs.

Flaring black holes may solve cosmic ray puzzle - New Scientist - New Scientist

Flaring black holes may solve cosmic ray puzzle: Then they found a clue: gamma-ray burst GRB110328A, which happened in March 2011. Its afterglow persisted for over a week, instead of a few hours like normal ones. The culprit was most likely a star falling into a galaxy's central black hole. This would make a weak black hole flare up, producing a burst of gamma rays that in turn spits out cosmic rays, suggests Farrar...

Neutrinos send wireless message through the Earth

Neutrinos send wireless message through the Earth: The researchers used Fermilab's Neutrinos at the Main Injector (NuMI) beam to fire pulses containing trillions of neutrinos at the MINERvA detector, which is underground so as to shield it from cosmic rays, charged particles that rain down on Earth from space. The team encoded the word "neutrino" using a standard binary communications code that turns letters into strings of zeros and ones. These binary digits were transmitted using the presence of a pulse to stand for "1" and the absence to stand for "0".

The one-word message consisted of 25 pulses separated by a space of just over two seconds and was repeated around 3500 times over a span of 142 minutes, with an average of just 0.81 neutrinos detected for each pulse. That corresponds to a transmission rate of 0.1 bits per second, with an error rate of 1 per cent.

Superconductor May Hide Long-sought Secret - Science News

Superconductor May Hide Long-sought Secret - Science News: To probe the material, Yoichi Ando of Osaka University and colleagues in Japan injected current into it using a gold wire. This excited electrons at the surface, creating ripples of energy. Conventional superconductors have a dead spot in their surfaces that prevents low-energy, slow-wobbling ripples from forming. But a close look at this material revealed a sea of waves bouncing up and down both quickly and slowly.

Ando says that this pattern of ripples is “unambiguous evidence” of a type of superconductivity never seen before: topological superconductivity, in which electrons become waves molded into a complex shape that resembles the outside of a doughnut. These waves, says Ando, seem to be behaving like exotic two-dimensional particles at the surface of the material — specifically, Majorana fermions.

“This is the best evidence so far for Majorana fermions in a solid material,” says Taylor Hughes, a theoretical physicist at the University of Illinois at Urbana-Champaign.

Faster-than-Light Neutrino Puzzle Claimed Solved by Special Relativity - Technology Review

Faster-than-Light Neutrino Puzzle Claimed Solved by Special Relativity - Technology Review: But the tricky part is keeping the clocks at either end exactly synchronised. The team does this using GPS satellites, which each broadcast a highly accurate time signal from orbit some 20,000km overhead. That introduces a number of extra complications which the team has to take into account, such as the time of travel of the GPS signals to the ground...
Although the speed of light is does not depend on the the frame of reference, the time of flight does. In this case, there are two frames of reference: the experiment on the ground and the clocks in orbit. If these are moving relative to each other, then this needs to be factored in...
Van Elburg calculates that it should cause the neutrinos to arrive 32 nanoseconds early. But this must be doubled because the same error occurs at each end of the experiment. So the total correction is 64 nanoseconds, almost exactly what the OPERA team observes.

Neutrinos Travel Faster Than Light, According to One Experiment - ScienceNOW

Neutrinos Travel Faster Than Light, According to One Experiment - ScienceNOW: Over 3 years, OPERA researchers timed the roughly 16,000 neutrinos that started at CERN and registered a hit in the detector. They found that, on average, the neutrinos made the 730-kilometer, 2.43-millisecond trip roughly 60 nanoseconds faster than expected if they were traveling at light speed. "It's a straightforward time-of-flight measurement..."
...the tricky part is accurately measuring the time between when the neutrinos are born by slamming a burst of protons into a solid target and when they actually reach the detector. That timing relies on the global positioning system, and the GPS measurements can have uncertainties of tens of nanoseconds. "I would be very interested in how they got a 10-nanosecond uncertainty, because from the systematics of GPS and the electronics, I think that's a very hard number to get."

Solar Interior May Reveal Modifications to Gravity - Technology Review

Solar Interior May Reveal Modifications to Gravity - Technology Review: In a weak gravitational field, like that inside the Earth, Einstein's equations reduce to their Newtonian equivalent and are well understood.
But in a much stronger field, the answer is not so clear cut because nobody knows how the distortion of spacetime occurs inside matter...
...these small modifications to gravity should influence the internal structure of the Sun and that we ought to be able to spot them with measurements we can make today...

Could the Big Bang have been a quick conversion of antimatter into matter?

Could the Big Bang have been a quick conversion of antimatter into matter?: ...Hajdukovic imagines the existence of a matter-antimatter repulsion that is significant only at short range; specifically, inside a black hole’s event horizon, or smaller than the Schwarzschild radius. Immediately after the gravitational Schwinger mechanism produces particle-antiparticle pairs, the repulsion force would cause a black hole to violently repel the opposite particle type. The result would be the conversion of nearly all matter into antimatter (or vice versa) in a very short time that depends on the size of the black hole.
Through calculations, Hajdukovic shows that the amount of matter that can be converted into antimatter (or vice versa) in one second could be up to 10128 kg, which is several orders of magnitude greater than the entire mass of the universe, about 1053 kg. If correct, it would mean that all of the matter in the universe could be converted into antimatter in a fraction of the Planck time...
... in his paper titled “Is dark matter an illusion created by the gravitational polarisation of the quantum vacuum,” he obtains a “striking equation” in agreement with observations and without invoking dark matter.

Dark-energy fingerprints found in ancient radiation - physics-math - 15 July 2011 - New Scientist

Dark-energy fingerprints found in ancient radiation: ...the accelerating expansion of the universe should prevent the growth of very massive structures. "In a universe with no dark energy, massive objects would just keep growing, which results in more gravitational lensing," says Sudeep Das of the University of California, Berkeley.

Gravitational lensing is tough to pick out in the ancient radiation because the CMB contains random fluctuations. But Das and his colleagues have used a new type of mathematical analysis to reveal for the first time the distinctive distortions from gravitational lensing in the CMB.

Gravity's bias for left may be writ in the sky - space - 05 March 2011 - New Scientist

Gravity's bias for left may be writ in the sky: The pair calculate that if gravity depended on just left or right-handed gravitons, that would have skewed the polarisation pattern in an obvious way. What's more, inflation would have stretched these effects to astronomical proportions, making them easily visible to astronomers...
Evidence of left-handed gravitons in the CMB would be "a triple discovery", says Lee Smolin of the Perimeter Institute in Waterloo, Ontario, Canada, who has worked with Magueijo and Benincasa on the subject. "It would confirm inflation, that gravity is quantum mechanical and that there is left-right asymmetry in quantum gravity."

Demons, Entropy, and the Quest for Absolute Zero: Scientific American

Demons, Entropy, and the Quest for Absolute Zero: Scientific American: For the one-way gate to work, I reasoned, the atoms in the gas must have two different states (possible configurations of orbiting electrons) that are both of low energy and thus stable. Let us call the two states blue and red. The atoms are suspended in a container that is cut across the middle by a laser beam. The beam is tuned to a wavelength that makes red atoms bounce back when they approach it, so that it acts in essence as a closed gate. Initially all atoms are blue and thus can fly through the laser barrier unimpeded. But just to the right of the barrier beam, atoms are hit by a second laser, this one tuned so that atoms turn from blue to red by scattering a single photon. Now the atoms, being red, are repelled by the barrier beam and thus cannot go through the gate and back to the left side. Eventually all the atoms gather up on the right side, and the left side remains empty.

Supernova To Superfluid - Science News

Supernova To Superfluid - Science News: Subsequent measurements revealed that its 2-million-degree surface had cooled by 4 percent over the decade since its discovery. “This was the first time anyone found a young neutron star clearly changing temperature,” says Craig Heinke, an astrophysicist at the University of Alberta in Edmonton, Canada, who reported the observations last year in Astrophysical Journal Letters.

Theorists had long speculated that a young neutron star should cool for the first 100 years after its creation. Neutrons can break down into protons, ejecting nearly massless particles called neutrinos that carry energy away from the star. But this energy-sapping Urca process (named for a money-sapping casino in Brazil) couldn’t account for the steep temperature drop seen by Chandra hundreds of years after the Cassiopeia supernova.

New Subatomic Particle Could Help Explain the Mystery of Dark Matter: Scientific American

New Subatomic Particle Could Help Explain the Mystery of Dark Matter: Scientific American: How did scientists go about looking for particles that are virtually undetectable? Kusenko and Michael Loewenstein of the NASA Goddard Space Flight Center reasoned that if sterile neutrinos really are dark matter, they would occasionally decay into ordinary matter, producing a lighter neutrino and an x-ray photon, and it would make sense to search for these x-rays wherever dark matter is found. Using the Chandra x-ray telescope, they observed a nearby dwarf galaxy thought to be rich in dark matter and found an intriguing bump of x-rays at just the right wavelength.

Physics experiment suggests existence of new particle

Physics experiment suggests existence of new particle: "Scientists previously believed three flavors of neutrino exist. In this Mini Booster Neutrino Experiment, dubbed MiniBooNE, researchers detected more oscillations than would be possible if there were only three flavors.
'These results imply that there are either new particles or forces we had not previously imagined,'"