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Polaritons are quasiparticles that are formed when photons couple strongly with excitations of matter. These quasi-particles, which are half-light and half-matter, underpin the functioning of a wide range of emergent photonic quantum systems, including semiconductor-based nanophotonic devices and circuit quantum electrodynamic systems.

Researchers at Stony Brook University have recently introduced a novel polariton system in which the matter excitation is replaced by an atom in an optical lattice and the photon by an atomic matter wave. This system, introduced in a paper published in Nature Physics, results in matter-wave polaritons, and could open interesting possibilities for the study of polaritonic quantum matter.

“A few years ago, we became interested in the idea of using ultracold atoms to simulate the dynamical behavior of ,” Dr. Dominik Schneble, head of the team of researchers who carried out the study, told Phys.org. “It turns out that it is possible to build an artificial atom that spontaneously emits matter waves, in much the same way as an atom spontaneously emits a photon (as described by the so-called Weisskopf-Wigner model).”

Josh SeehermanI don’t think he’s wrong.

Walter Lynsdale” agreeing with a Twitter user who said the “Woke mind virus is the biggest threat to civilization,”

… not nuclear war, or fossil fuel dependence? 😕

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This menagerie includes three spiral-shaped galaxies, an elliptical galaxy, and a lenticular (lens-like) galaxy. Somehow, these different galaxies crossed paths in their evolution to create an exceptionally crowded and eclectic galaxy sampler.

Caught in a leisurely gravitational dance, the whole group is so crowded that it could fit within a region of space that is less than twice the diameter of our Milky Way.

The Milky Way is the galaxy that contains the Earth, and is named for its appearance from Earth. It is a barred spiral galaxy that contains an estimated 100–400 billion stars and has a diameter between 150,000 and 200,000 light-years.

Traditionally, research showed tumor tissue to be free of microbes. In recent years, however, technology has advanced, allowing scientists to detect tiny numbers of bacteria that have taken up residence inside tumor tissue. For example, Shang Cai and his team detected 135,000 microorganisms in a gram of mouse breast tumor tissue, almost ten times more than in healthy tissue. (By comparison, a gram of feces has roughly 300 billion microbes.) Furthermore, nearly all the bacteria were living inside the mouse cells.

The biological significance of the intratumor microbiota remains largely unknown. However, scientists have found that the gut microbiota contributes to tumor progression. Cai wanted to know if these tumor-infesting intracellular bacteria are also involved in cancer progression.

Oxford University researchers have developed a sensor made of sapphire fiber that can tolerate extreme temperatures, with the potential to enable significant improvements in efficiency and emission reduction in aerospace and power generation.

The work, published in the journal Optics Express, uses a sapphire —a thread of industrially grown sapphire less than half a millimeter thick—which can withstand temperatures over 2000°C. When light is injected onto one end of the sapphire fiber, some is reflected back from a point along the fiber which has been modified to be sensitive to temperature (known as a Bragg grating). The wavelength (color) of this reflected light is a measure of the temperature at that point.

The research resolves a 20-year-old problem with existing sensors—while the sapphire fiber seems very thin, in comparison to the wavelength of light it is huge. This means that the light can take many different paths along the sapphire fiber, which results in many different wavelengths being reflected at once. The researchers overcame this problem by writing a channel along the length of the fiber, such that the light is contained within a tiny cross-section, one-hundredth of a millimeter in diameter. With this approach, they were able to make a sensor that predominantly reflects a single wavelength of light.

How China can boost its carbon neutrality efforts by ensuring renewables account for more than 50% of the power supply for aluminium production by 2045.


Decarbonizing the power supply for primary aluminium is critical for the sector to reach net zero. Electricity used during aluminium smelting – the process of extracting the metal from its ore – accounts for more than 60% of the industry’s carbon emissions.

It is particularly important to control the carbon emissions of China’s production of primary aluminium, which comes directly from mined ore rather than using recycled or alloy materials. Primary aluminium produced and consumed in China accounts for approximately 60% of the global market. Due to the high proportion of coal-fired energy used, 12.7 tonnes of carbon is emitted per tonne of aluminium produced in China, versus a global average of 10.3 tonnes, according to the latest figures, which cover the 2005 to 2019 period. This is why decarbonizing the power supply for Chinese primary aluminium production is critical.