Lifeboat Foundation

Linear analysis plays a central role in science and engineering. Even when dealing with nonlinear systems, understanding the linear response is often crucial for gaining insight into the underlying complex dynamics. In recent years, there has been a great interest in studying open systems that exchange energy with a surrounding reservoir. In particular, it has been demonstrated that open systems whose spectra exhibit non-Hermitian singularities called exceptional points can demonstrate a host of intriguing effects with potential applications in building new lasers and sensors.

At an exceptional point, two or modes become exactly identical. To better understand this, let us consider how drums produce sound. The membrane of the drum is fixed along its perimeter but free to vibrate in the middle.

As a result, the membrane can move in different ways, each of which is called a mode and exhibits a different sound frequency. When two different modes oscillate at the same frequency, they are called degenerate. Exceptional points are very peculiar degeneracies in the sense that not only the frequencies of the modes are identical but also the oscillations themselves. These points can exist only in open, non-Hermitian systems with no analog in closed, Hermitian systems.

A multidisciplinary team of Indiana University researchers have discovered that the motion of chromatin, the material that DNA is made of, can help facilitate effective repair of DNA damage in the human nucleus—a finding that could lead to improved cancer diagnosis and treatment. Their findings were recently published in the Proceedings of the National Academy of Sciences.

DNA damage happens naturally in human body and most of the damage can be repaired by the cell itself. However, unsuccessful repair could lead to cancer.

“DNA in the nucleus is always moving, not static. The motion of its high-order complex, chromatin, has a direct role in influencing DNA repair,” said Jing Liu, an assistant professor of physics in the School of Science at IUPUI. “In yeast, past research shows that DNA damage promotes chromatin motion, and the high mobility of it also facilitates the DNA repair. However, in human cells this relationship is more complicated.”

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Future lunar missions will be able to find acceptable spots thanks to the knowledge they have gained about the region’s physical properties.

The newly-discovered neuronal back-up system safeguards metabolic flexibility of neurons to cope with energy demands of electrical signaling, according to a team of researchers from the Center of Physiology and Pharmacology at the Medical University of Vienna.

If one of these systems fails, another one takes over and ensures that sufficient energy is supplied to meet the prevailing requirement.

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The Nobel prize in physics this year went to black holes. Generally speaking. Specifically, it was shared by the astronomers who revealed to us the Milky Way’s central black hole and by Roger Penrose, who proved that in general relativity, every black hole contains a place of infinite gravity — a singularity. But the true impact of Penrose’s singularity theorem would is much deeper — it leads us to the limits Einstein’s great theory and to the origin of the universe.

Continue reading “How The Penrose Singularity Theorem Predicts The End of Space Time” »

The company behind Facebook has created an AI that could one day be used to help nonverbal people better communicate.

The infrared (IR) spectrum is a vast information landscape that modern IR detectors tap into for diverse applications such as night vision, biochemical spectroscopy, microelectronics design, and climate science. But modern sensors used in these practical areas lack spectral selectivity and must filter out noise, limiting their performance. Advanced IR sensors can achieve ultrasensitive, single-photon level detection, but these sensors must be cryogenically cooled to 4 K (−269 C) and require large, bulky power sources making them too expensive and impractical for everyday Department of Defense or commercial use.

DARPA’s Optomechanical Thermal Imaging (OpTIm) program aims to develop novel, compact, and room-temperature IR sensors with quantum-level performance – bridging the performance gap between limited capability uncooled thermal detectors and high-performance cryogenically cooled photodetectors.

“If researchers can meet the program’s metrics, we will enable IR detection with orders-of-magnitude improvements in sensitivity, spectral control, and response time over current room-temperature IR devices,” said Mukund Vengalattore, OpTIm program manager in DARPA’s Defense Sciences Office. “Achieving quantum-level sensitivity in room-temperature, compact IR sensors would transform battlefield surveillance, night vision, and terrestrial and space imaging. It would also enable a host of commercial applications including infrared spectroscopy for non-invasive cancer diagnosis, highly accurate and immediate pathogen detection from a person’s breath or in the air, and pre-disease detection of threats to agriculture and foliage health.”

This user-processed NIRCam image of a glittering star field shows that Reddit is the gift that keeps on giving for Webb Space Telescope fans.

We could one day charge our phones and tablets wirelessly through the air, thanks to newly developed technology.

Researchers have used infrared laser light to transmit 400mW of light power over distances of up to 30 meters (98 feet). That’s enough juice to charge small sensors, though in time it could be developed to charge up larger devices such as smartphones too.

All this is done in a way which is perfectly safe – the laser falls back to a low power mode when not in use.