Quantum split: Particle this way, properties that way - physics-math - 23 July 2014 - New Scientist

Quantum split: Particle this way, properties that way - physics-math - 23 July 2014 - New Scientist: In Grenoble, the Vienna team used a feeble magnetic field and a weakly interacting neutron absorber to make the weak measurements. They found that when they put the absorber in one path of the interferometer (say left), there was a discernible effect at the output. But when they put it in the right path, it had no such effect. The neutrons were travelling in one path only.

Next, the experimenters introduced a weak magnetic field near each arm of the interferometer, to interact with the spin of the neutrons. When they did this in the left path, there was no change in the interferometer's output. If they introduced the magnetic field in the right path, though, there was a change: the magnetic field had interacted with the spin. In other words, they had confirmed that the spin had chosen the path not taken by the parent neutron...

Two-laser boron fusion lights the way to radiation-free energy : Nature News & Comment

Two-laser boron fusion lights the way to radiation-free energy : Nature News: One laser created a short-lived plasma, or highly ionized gas of boron nuclei, by heating boron atoms; the other laser generated a beam of protons that smashed into the boron nuclei, releasing slow-moving helium particles but no neutrons...

The boron plasma generated by the laser lasts only about one-billionth of a second, and so the pulse of protons, which lasts one-trillionth of a second, must be precisely synchronized to slam into the boron target. The proton beam is preceded by a beam of electrons, generated by the same laser, that pushes away electrons in the boron plasma, allowing the protons more of a chance to collide with the boron nuclei and initiate fusion.

New evidence to aid search for charge 'stripes' in superconductors

New evidence to aid search for charge 'stripes' in superconductors: ...uncovering the detailed relationship between these stripe patterns and the appearance or disappearance of superconductivity is extremely difficult, particularly because the stripes that may accompany superconductivity are very likely moving, or fluctuating.


The scientists ground up crystals of the test material into a fine powder and placed samples of it in line with a beam of neutrons...


With increasing temperature, the scientists found that while the aspect ratio of the crystal structure changed, the displacements from average structure persisted, leading them to conclude by inference that the striped pattern of charge density also remained, even though it was no longer static.

"This is the first powder diffraction scattering evidence for fluctuating charge stripes above the temperature where we see static order..."

Theory Explains the Quantum Weirdness of Exotic Materials | Wired Science | Wired.com

Theory Explains the Quantum Weirdness of Exotic Materials | Wired Science | Wired.com: Physicists have now developed a mathematical theory that describes how collective quantum mechanical weirdness leads to the strange properties of these materials. While previous work has focused on each individual system, the new theory unites the behavior for many materials, including magnets, superfluids, and neutron star matter...
Murayama and his graduate student, Haruki Watanabe, showed that the behavior of these materials hinges on a phenomenon known as spontaneous symmetry breaking...

Are neutrons traveling between parallel worlds?

Are neutrons traveling between parallel worlds?: Recent experiments at ultra-cold temperatures have shown a phenomenon known as "neutron loss," in which we somehow lose track of these subatomic particles for short periods. This probably has a mundane explanation...but just for fun, here's an awesomely insane explanation.

Experiments Show Gravity Is Not an Emergent Phenomenon� - Technology Review

Experiments Show Gravity Is Not an Emergent Phenomenon� - Technology Review:  Kobakhidze argues that since each quantum particle must be described by a large number of other particles, this leads to a particular equation that describes the effect of gravity.

But here's the thing: the conventional view of gravity leads to a different equation...

As it happens, physicists have been measuring the force of gravity on neutrons for ten yeas or so. And...wait for the drum roll... the results exactly match the predictions of traditional gravitational theory, says Kobakhidze.

Neutron analysis reveals '2 doors down' superconductivity link

Neutron analysis reveals '2 doors down' superconductivity link: "As we analyze the spectra, we find that even though the nearest neighbor exchange couplings between chalcogenide and pnictide atoms are different, the next nearest neighbor exchange couplings are closely similar," said Pengcheng Dai, who has a joint appointment with ORNL's Neutron Sciences Directorate and the University of Tennessee.
Dai referred to theories that have suggested second-nearest-neighbor couplings could be responsible for the widely acclaimed but poorly understood properties of high-temperature superconductors.

Bound neutrons pave way to free ones

Bound neutrons pave way to free ones: "'Take a quantity that tells you how strong the EMC Effect is. And then take another quantity that tells you how many short-range correlations you have,' Higinbotham explains. 'And you see that when one is big, the other one is big. When one is small, the other one is small.'
The scientists say that it's unlikely that one effect causes the other. Rather, the data shows that there is a common cause for both."

Neutron star seen forming exotic new state of matter - space - 04 February 2011 - New Scientist

Neutron star seen forming exotic new state of matter: It has long been assumed that neutrons in the cores of neutron stars become superfluid, but without any direct evidence that they do so. That changed in 2010, when astrophysicists Craig Heinke and Wynn Ho examined measurements taken by NASA's orbiting Chandra X-ray Observatory of the 330-year-old neutron star at the heart of the dusty supernova remnant Cassiopeia A...

These measurements show the star has dimmed by 20 per cent since it was discovered in 1999, corresponding to an estimated temperature drop of 4 per cent. "It's enormously fast cooling," says Dany Page of the National Autonomous University of Mexico in Mexico City.

Imaging with neutrons: Magnetic domains shown for the first time in 3-D

Imaging with neutrons: Magnetic domains shown for the first time in 3-D: "Magnetic fields deflect the neutrons slightly from their flight path, just as water diverts light. An object under water cannot be directly perceived because of this phenomenon; the object appears distorted and in a different location. Similarly, the neutrons pass through domain walls along their path through the magnetic material. At these walls, they are diverted into different directions.
This diversion, however, is only a very weak effect. It is typically invisible in a neutron radiogram, since it is overshadowed by non-diverted rays. The researchers therefore employ several diffraction gratings in order to separate the diverted rays. During a measurement, they rotate the sample and shoot rays through it from all directions. From the separated rays, they can calculate all domain shapes and generate an image of the domain network in its entirety."