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The two stars take about 20.5 hours to revolve around each other.

Astrophysicists of the University of California San Diego (UC San Diego) and Northwestern University have discovered the most compact ultracool dwarf binary system known to date using W. M. Keck Observatory on Maunakea, Hawaii Island.

Named LP 413-53AB, this newly discovered system comprises two ultracool dwarfs, the category of stars which are extremely low in mass and emit light mainly in the infrared because of their low temperature.

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Saad Bhamla was in his backyard when he noticed something he had never seen before: an insect urinating. Although nearly impossible to see, the insect formed an almost perfectly round droplet on its tail and then launched it away so quickly that it seemed to disappear. The tiny insect relieved itself repeatedly for hours.

It’s generally taken for granted that what goes in must come out, so when it comes to fluid dynamics in animals, the research is largely focused on feeding rather than excretion. But Bhamla, an assistant professor in the School of Chemical and Biomolecular Engineering at the Georgia Institute of Technology, had a hunch that what he saw wasn’t trivial.

“Little is known about the fluid dynamics of excretion, despite its impact on the morphology, energetics, and behavior of animals,” Bhamla said. “We wanted to see if this tiny insect had come up with any clever engineering or physics innovations in order to pee this way.”

Died: 21 November 1970, Bangalore, India.

Affiliation at the time of the award: Calcutta University, Calcutta, India.

Prize motivation: “for his work on the scattering of light and for the discovery of the effect named after him”

Physicists in West Virginia have announced a potential breakthrough that could help upend a longstanding constraint imposed by the first law of thermodynamics.

The discovery, involving how energy is converted in plasmas in space, was described in new research published in the journal Physical Review Letters, and could potentially require scientists to have to rethink how plasmas are heated both in the lab and in space.

The first law of thermodynamics, an expression of the law of conservation of energy albeit styled with relation to thermodynamic processes, conveys that the total energy within a system will remain constant, but that it can be converted from one form of energy into another. More simply, the idea is commonly expressed as “energy can neither be created or destroyed.”

Atomic nuclei take a range of shapes, from spherical (like a basketball) to deformed (like an American football). Spherical nuclei are often described by the motion of a small fraction of the protons and neutrons, while deformed nuclei tend to rotate as a collective whole.

A third kind of motion has been proposed since the 1950s. In this motion, known as nuclear vibration, atomic nuclei fluctuate about an average shape. Scientists recently investigated cadmium-106 using a technique called Coulomb excitation to probe its nuclear shape. They found clear experimental evidence that the vibrational description fails for this isotope’s nucleus. This finding is counter to the expected results.

Research published in Physics Letters B builds on a long quest to understand the transition between spherical and deformed nuclei. This transition often includes vibrational motion as an intermediate step. The new result suggests that nuclear physicists may need to revise the long-standing paradigm describing how this transition occurs.

Recently, a research team led by Prof. Guo Guangcan from the University of Science and Technology of China (USTC) constructed a non-Hermiticity (NH) synthetic orbital angular momentum (OAM) dimension in a degenerate optical cavity and observed the exceptional points (EPs). This study was published in Science Advances.

In topological physics, the NH systems depict open systems with complex energy spectra. Exceptional points are one of the unique features of NH systems. To study EPs, the team had constructed synthetic one-dimensional lattices and established topological simulation platform in a degenerate optical cavity. Based on this platform, an additional pseudomomentum was introduced as a parameter to construct the Dirac point in the two-dimensional momentum space. A pair of EPs can be obtained by introducing non-Hermitian perturbation around the Dirac point.

The detection of complex energy spectra in NH systems can be troublesome for traditional means. The research group developed a method which is referred to as wave front angle–resolved band structure spectroscopy to investigate complex energy spectra based on synthetic OAM. Using this method, the team not only detected EPs in momentum space, but also the key features of EPs like bulk Fermi arcs, parity-time symmetry-breaking transition, energy swapping and half-integer band windings.

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Was awarded to James Chadwick ‘for the discovery of the neutron’.

Author Heinrich Päs shares 5 key insights from his new book, The One: How an Ancient Idea Holds the Future of Physics.