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Find out how traveling faster than light and traveling back in time are the same thing. And be sure to tell PBS what types of shows you want to see at https://www.surveymonkey.com/r/pbsds2017 25 random participants in the survey will receive PBS t-shirts.

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Physicists have simulated a black hole in a lab. Then it started glowing.

This allowed the team to realise that their black hole analogue may help explain so-called “Hawking radiation”, theorised to be emitted by black holes in nature.

Their analysis of the black hole in a bottle is presented in a paper published in the Physical Review Research journal.

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The universe is going to end. But of all the possible ends of the universe vacuum decay would have to be the most thorough — because it could totally rewrite the laws of physics. Today I hope to help you understand exactly how terrified you should be.

Continue reading “How Vacuum Decay Would Destroy The Universe” »

Carl knox / ozgrav, ARC centre of excellence for gravitational wave discovery, swinburne university of technology.

The specific event they observed and analyzed is so rare that it has only been seen three other times throughout history.

Scientists have created, synthesized, and analyzed a new class of fluorophores, which are luminous chemical compounds. These are the new bullet systems based on cyanopyrazine. According to research, the inclusion of cyanogroup compounds in fluorophores considerably boosts the efficiency of organic light-emitting diodes (OLED). This indicates they can be utilized to develop new materials to improve the brightness of smartphone, computer, and television screens. The researchers’ findings were recently published in the journal Dyes and Pigments.

The research was led by Egor Verbitskiy, the director of the Postovsky Institute of Organic Synthesis Ural Branch of RAS and a member of the Laboratory of Medical Chemistry and Advanced Organic Materials at the Ural Federal University. He states that physicists were aware that introducing cyanogroups to fluorophores can enhance the OLEDs’ properties and overall efficiency.

An analysis of star clusters suggests that some of them are apparently defying the known laws of physics, leaving experts baffled.

Walking can boost not only your own energy but also, potentially, the energy of your wearable electronic devices. Osaka Metropolitan University scientists made a significant advance toward self-charging wearable devices with their invention of a dynamic magnifier-enhanced piezoelectric vibration energy harvester that can amplify power generated from impulsive vibrations, such as from a human walking, by about 90 times, while remaining as small as currently developed energy harvesters. The results were published in Applied Physics Letters.

These days, people carry multiple electronic devices such as smartphones, and wearable devices are expected to become increasingly widespread in the near future. The resulting demand for more efficient recharging of these devices has increased the attention paid to energy harvesting, a technology that converts energy such as heat and light into electricity that can power small devices. One form of energy harvesting called vibration energy harvesting is deemed highly practical given that it can transform the kinetic energy from vibration into electricity and is not affected by weather or climate.

A research team led by Associate Professor Takeshi Yoshimura from the Graduate School of Engineering at Osaka Metropolitan University has developed a microelectromechanical system (MEMS) piezoelectric vibration energy harvester that is only approximately 2 cm in diameter with a U-shaped metal component called a dynamic magnifier. Compared with conventional harvesters, the new harvester allows for an increase of about 90 times in the power converted from impulsive vibrations, which can be generated by the human walking motion.

“Thermal issues are currently one of the biggest bottlenecks that are plaguing any kind of microelectronics,” says team lead Srabanti Chowdhury, professor of electrical engineering at Stanford University. “We asked ourselves, ‘Can we perform device cooling at the very material level without paying a penalty in electrical performance?’”

Indeed, they could. The engineers grew a heat-wicking diamond layer right on top of individual transistors—their hottest points—as well as on their sides. Heat flowed through the diamond to a heat sink on the back of the device. With this technique, the researchers achieved temperatures 100 degrees Celsius lower without any degradation of the device’s electrical properties. They will report their findings in San Francisco at the IEEE International Electron Device Meeting in December.

They demonstrated their technique on gallium nitride (GaN) high-electron-mobility transistors, or HEMTs. GaN is the go-to alternative to silicon for high-frequency applications, as it can sustain higher electric fields and responds more quickly to electric field changes. GaN also breaks down at a higher temperature than silicon. But not high enough: “If you go by the physics of the material, you see what its potential is, and we’re nowhere close to that today,” says Chowdhury. Keeping GaN HEMTs cool as devices shrink and frequencies grow will allow them to live up to their physics-promised potential.

Workshop supported by the Imperial College Physics of Life Network of Excellence.

https://www.imperial.ac.uk/physics-of-life/

Continue reading “Physics of Emergent Behaviour III: from origin of life to multicellularity, 2nd July 2021 (part 2)” »