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Feb 21, 2023

Researchers at Purdue unlock light-matter interactions on sub-nanometer scales, leading to ‘picophotonics’

Posted by in categories: materials, quantum physics

Researchers at Purdue University have discovered new waves with picometer-scale spatial variations of electromagnetic fields which can propagate in semiconductors like silicon. The research team, led by Dr. Zubin Jacob, Elmore Associate Professor of Electrical and Computer Engineering and Department of Physics and Astronomy (courtesy) published their findings in APS Physics Review Applied in a paper titled, “Picophotonics: Anomalous Atomistic Waves in Silicon.”

“The word microscopic has its origins in the length scale of a micron which is a million times smaller than a meter. Our work is for light matter interaction within the picoscopic regime which is far smaller, where the discrete arrangement of atomic lattices changes light’s properties in surprising ways.” says Jacob.

These intriguing findings demonstrate that natural media host a variety of rich light-matter interaction phenomena at the atomistic level. The use of picophotonic waves in semiconducting materials may lead researchers to design new, functional optical devices, allowing for applications in quantum technologies.

Feb 21, 2023

Prolonged microgravity induces reversible and persistent changes on human cerebral connectivity

Posted by in category: neuroscience

Rs-fMRI is used to investigate human brain connectivity changes induced by prolonged microgravity in cosmonauts before and after spaceflight, with both persistent and reversible location specific changes in connectivity being observed.

Feb 21, 2023

Study shows that distinct pyramidal cell types drive different patterns of cortical activity during decision-making

Posted by in categories: genetics, neuroscience

The outer layer of the brain, known as the cortex, is made of different types of neurons. Neuroscience studies suggest that these different neuron types have distinct functions, yet for a long time this was difficult to ascertain, due to the inability to examine and manipulate them in the brains of living beings.

In recent years, opened new possibilities for studying cells and their functions. Using some of these techniques, researchers at Forschungszentrum Jülich, RWTH Aachen University, Cold Spring Harbor Laboratory and other institutes in the United States closely examined the functions of different pyramidal cells, which are commonly found in the human cortex.

Their findings, published in Nature Neuroscience, suggest that distinct types of pyramidal cells drive patterns of cortical activity associated with different functions. The team’s study builds on some of their previous works focusing on in the cortex.

Feb 21, 2023

Physicists make most precise measurement yet of magnetic moment of an electron

Posted by in category: physics

A combined team of physicists from Harvard University and Northwestern University has found the most precise value yet for the magnetic moment of an electron. In their paper published in the journal Physical Review Letters, the group describes the methods they used to measure properties of an electron and implications of the new precision.

The of an electron, also known as the electron , results from its electric and spin properties. Of all the elementary properties that have been studied, it is the one that has been the most precisely measured, and also the most accurately verified.

Measuring the magnetic moment of an electron to ever higher standards of accuracy is important because physicists believe that at some point, such measurements will help to complete the standard model of physics. In this new effort, the research group has measured the magnetic moment to a precision twice that of any other effort—the last best effort was 14 years ago.

Feb 21, 2023

Large language models generate functional protein sequences across diverse families

Posted by in categories: biological, robotics/AI, singularity

“A language model AI created proteins as good as ones honed over a million years of evolution. The implications are staggering” o.o Basically this leads to possibly a biological singularity:3.


A generative deep-learning model designs artificial proteins with desired enzymatic activities.

Feb 21, 2023

Why do black holes twinkle?

Posted by in category: cosmology

Black holes are bizarre things, even by the standards of astronomers. Their mass is so great, it bends space around them so tightly that nothing can escape, even light itself.

And yet, despite their famous blackness, some black holes are quite visible. The gas and stars these galactic vacuums devour are sucked into a glowing disk before their one-way trip into the hole, and these disks can shine more brightly than entire galaxies.

Stranger still, these black holes twinkle. The brightness of the glowing disks can fluctuate from day to day, and nobody is entirely sure why.

Feb 21, 2023

Space debris apocalypse: 6 objects that could wreak havoc in Earth’s orbit

Posted by in category: satellites

The space around our planet is getting cluttered. Thousands of satellites and millions of out-of-control fragments of space debris hurtle high above our heads, threatening to collide. Here are the objects that experts fear the most.

In just the past month, the goings-on in near-Earth space have twice made headlines and prompted experts to call for action. On Jan. 27, space debris researchers looked on in horror as two huge pieces of space junk ⁠— a decades-old upper stage of a Russian rocket and a long-defunct Russian satellite — came within 20 feet (6 meters) or so of each other. The incident, described as a close call “worst case scenario,” could have spawned thousands of dangerous debris fragments that would have stayed in orbit for centuries. Then, a report released on Feb. 6 revealed that in early January a mysterious Russian satellite broke apart into 85 fragments large enough to be tracked from Earth.

Feb 21, 2023

David Hilbert — The Foundations of Geometry

Posted by in categories: mathematics, space

David Hilbert was a great leader and spokesperson for the discipline of mathematics in the early 20th Century. But he was an extremely important and respected mathematician in his own right.

Like so many great German mathematicians before him, Hilbert was another product of the University of Göttingen, at that time the mathematical centre of the world, and he spent most of his working life there. His formative years, though, were spent at the University of Königsberg, where he developed an intense and fruitful scientific exchange with fellow mathematicians Hermann Minkowski and Adolf Hurwitz.

Sociable, democratic and well-loved both as a student and as a teacher, and often seen as bucking the trend of the formal and elitist system of German mathematics, Hilbert’s mathematical genius nevertheless spoke for itself. He has many mathematical terms named after him, including Hilbert space (an infinite dimensional Euclidean space), Hilbert curves, the Hilbert classification and the Hilbert inequality, as well as several theorems, and he gradually established himself as the most famous mathematician of his time.

Feb 21, 2023

What Do The Reconstructed Brains of 125-Million-Year-Old Spinosaurs Tell Us?

Posted by in category: neuroscience

A study suggests that the spinosaurs’ brains weren’t specialized for their semi-aquatic lifestyles.

Feb 21, 2023

Zigzags on a Shell From Java Are the Oldest Human Engravings

Posted by in category: futurism

On the banks of the Solo River in Java, Indonesia, 19th-century physician Eugene Dubois uncovered an astounding fossil find: the bones of what appeared to be an ancient human, surrounded by animal remains and shells. Excavated in the 1890s, the site gained fame as the home of “Java Man,” better known today as Homo erectus.

Dated to between a million and 700,000 years old, the bones immediately provoked controversy, because Dubois claimed they showed evidence of a transitional species between apes and humans. It turns out he was right— Homo erectus fossils have since been found in Africa and elsewhere in Asia, and it is possible the species is a direct ancestor of our own. But it’s the palm-sized shells found alongside the Java remains that are raising big questions today. An examination of the shells published in Nature suggests that Homo erectus may have used the shells for tools and decorated some of them with geometric engravings. At around half a million years old, the shells represent the earliest evidence of such decorative marks and also the first known use of shells to make tools.

Dubois collected 11 species of freshwater shells at the site, called Trinil. Most of them belong to the sub-species Pseudodon vondembuschianus trinilensis, a now extinct freshwater mussel he described in 1908. Initially scientists thought the mollusks had naturally clustered at the site, perhaps driven by water currents. Even without a connection to the human fossil, the cache provided a nice census of ancient freshwater shell life, coming from at least 166 Pseudodon individuals.