Physics

Albert Einstein’s theory of general relativity has fascinated physicists and generated debate about the origin of the universe and the structure of objects like black holes and complex stars called quasars. A major focus has been on confirming the existence of the gravitomagnetic field, as well as gravitational waves.

A physicist at the University of Missouri-Columbia recently argued in a paper that the interpretation of the results of Lunar Laser Ranging (LLR), which is being used to detect the gravitomagnetic field, is incorrect because LLR is not currently sensitive to gravitomagnetism and not effective in measuring it.

The large molecular gas cloud in the constellation of Taurus is the nearest star formation region and a star formation test environment for expert theorists and observers alike. The XMM-Newton project has provided by far the most sensitive and comprehensive X-ray survey of this region, for the first time systematically detecting almost all young stars embedded in the cloud as X-ray sources, including many objects with the lowest mass, the so-called brown dwarfs, and stars still in the process of growing, the so-called protostars.

Recent discoveries regarding the physics of ceramic superconductors may help improve scientists' understanding of resistance-free electrical power.

Tiny, isolated patches of superconductivity exist within these substances at higher temperatures than previously were known, according to a paper by Princeton scientists, who have developed new techniques to image superconducting behavior at the nanoscale.


Using a customized microscope, Princeton scientists have mapped the strength of current-carrying electron pairs as they form in a ceramic superconductor. From the top left, the images show the same 30-nanometer square region of the ceramic at successively cooler temperatures.

Sound waves escaping the sun's interior create fountains of hot gas that shape and power a thin region of the sun's atmosphere which appears as a ruby red "ring of fire" around the moon during a total solar eclipse, according to new research.

This region, called the chromosphere because of its color, is largely responsible for the deep ultraviolet radiation that bathes the Earth, producing the atmosphere's ozone layer.


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Physicists at the National Institute of Standards and Technology (NIST) have demonstrated a novel way of making atoms interfere with each other, recreating a famous experiment originally done with light while also making the atoms do things that light just won't do.

Their experiments showcase some of the extraordinary behavior taken for granted in the quantum world—atoms acting like waves and appearing in two places at once, for starters—and demonstrate a new technique that could be useful in quantum computing with neutral atoms and further studies of atomic hijinks.


Atoms interfering with themselves.

Silicon is the most important material for electronic chips and processors. Yet it has a big drawback: being a so-called indirect semiconductor, it hardly emits any light. Therefore worldwide efforts in the labs of the microelectronics industry are aimed towards developing more efficient light sources based on silicon. Physicists at the Forschungszentrum Dresden-Rossendorf (FZD) now managed to make Silicon shine red and blue in an alternating fashion. This two-color light source could help to produce cheap and compact biosensors.

Capturing the coldest atoms in the universe within the confines of a laser beam, University of California, Berkeley, physicists have made a device that can map magnetic fields more precisely than ever before.

Doctors now use sensitive magnetic field detectors called SQUIDS to record faint magnetic activity in the brain, while similar detectors are employed in fields ranging from geology to semiconductor manufacturing.

Physicists at the University of Pittsburgh have demonstrated a new form of matter that melds the characteristics of lasers with those of the world’s best electrical conductors. The work introduces a new method of moving energy from one point to another as well as a low-energy means of producing a light beam like that from a laser.

At proper frequencies, air itself can make information transmissions difficult to intercept. Stability of the signal is a problem in applications such as that but researchers at NIST have discovered a technique they say will preserve signals better.

Their fiber-optic network that can be tuned across a range of visible and near-infrared frequencies while synchronizing the oscillations of light waves from different sources.

Combining diamond anvils and powerful lasers, laboratory researchers have developed a technique that should be able to squeeze materials to pressures 100 to 1,000 times greater than possible today, reproducing conditions expected in the cores of supergiant planets.

Until now, these pressures have only been available experimentally next to underground nuclear explosions.