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A University of Illinois at Urbana-Champaign professor who argues for a “movement against objects, truths, and knowledge” will be leading a confab at Minnesota’s Carleton College this October. Carleton’s convocation series, described as “a shared campus experience that brings students, faculty, and staff together for […] a lecture or presentation from specialists in a variety of disciplines,” have “a rich history” dating back to the early 1940s The relationship between humans, mathematics, and the planet has been one steeped too long in domination and destruction […] Drawing upon Indigenous worldviews to reconceptualize what mathematics is and how it is practiced,...

Inventors of centuries past and scientists of today have found ingenious ways to make our lives better with magnets – from the magnetic needle on a compass to magnetic data storage devices and even MRI body scan machines. All of these technologies rely on magnets made from solid materials. But what if you could make a magnetic device out of liquids? Using a modified 3D printer, a team of scientists at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have done just that. Their findings, to be published July 19 in the journal Science, could lead to a...

The fact that no one has died from being struck by dark matter is enough proof to rule out certain ideas about the mysterious stuff, according to one new theory paper. There’s a conundrum facing physicists: Most of the universe’s mass appears to be missing, based on observations of the universe’s structure, how galaxies move, and how they seem to warp distant light. Thousands of physicists are now hunting for what might be producing these effects. But the mere fact that we’re alive here on Earth can offer some insight as to what dark matter isn’t, and the researchers behind...

These galaxies are selected from a Hubble Space Telescope program to measure the expansion rate of the universe, called the Hubble constant. The value is calculated by comparing the galaxies' distances to the apparent rate of recession away from Earth (due to the relativistic effects of expanding space). By comparing the apparent brightnesses of the galaxies' red giant stars with nearby red giants, whose distances were measured with other methods, astronomers are able to determine how far away each of the host galaxies are. This is possible because red giants are reliable milepost markers because they all reach the same...

The more entanglement in the so-called Hilbert space—the realm where quantum information processing can take place—the better. Previous photonic approaches were able to reach 18 qubits encoded in six entangled photons in the Hilbert space. Purdue researchers maximized entanglement with a gate using four qudits—the equivalent of 20 qubits—encoded in only two photons. In quantum communication, less is more. "Photons are expensive in the quantum sense because they're hard to generate and control, so it's ideal to pack as much information as possible into each photon," said Poolad Imany, a postdoctoral researcher in Purdue's School of Electrical and Computer Engineering....

A recent test has confirmed the predictions of quantum trajectory theory, which describes what happens during the long-mysterious “collapse” of a quantum system.Imagine if all our scientific theories and models told us only about averages: if the best weather forecasts could only give you the average daily amount of rain expected over the next month, or if astronomers could only predict the average time between solar eclipses. In the early days of quantum mechanics, that seemed to be its inevitable limitation: It was a probabilistic theory, telling us only what we will observe on average if we collect records for...

NASA’s Hubble telescope has recently discovered a supermassive black hole that defies existing theories about the universe, a report said. The black hole, which is about 250 million times heavier [more massive] than the sun, lies at the heart of the spiral galaxy NGC 3147 and is 140 million light-years from Earth. The Hubble telescope has detected a supermassive black hole that technically shouldn't exist, according to new findings. Spotted around the black hole was a thin “accretion disk” containing debris and gas rapidly pacing around the edge, according to findings published Thursday in the journal Monthly Notices of the...

Some of the greatest unanswered questions about the nature of the universe are related to light, the vacuum (i.e. space where neither matter nor radiation exists), and their relationship with time. In the past, physicists and philosophers have addressed a variety of complex questions, for instance, what is the nature of the vacuum, and how is the propagation of light connected to the passing of time? Researchers at the University of Konstanz have recently carried out a study exploring the quantum states of light and vacuum fluctuations, as well as their interplay with time. Their paper, published in Nature Physics,...

Australian researchers describe the first observation of a native ferroelectric metal: a native metal with bistable and electrically switchable spontaneous polarization states—the hallmark of ferroelectricity. The study found coexistence of native metallicity and ferroelectricity in bulk crystalline tungsten ditelluride (WTe2) at room temperature. A van-der-Waals material that is both metallic and ferroelectric in its bulk crystalline form at room temperature has potential for nano-electronics applications. The study represents the first example of a native metal with bistable and electrically switchable spontaneous polarization states—the hallmark of ferroelectricity. "We found coexistence of native metallicity and ferroelectricity in bulk crystalline tungsten ditelluride (WTe2)...

Between May 29 and July 1919, an expedition organized by Cambridge astronomer Arthur Eddington and the Astronomer Royal Frank Dyson photographed first an eclipse of the Sun (May 29) and then, a month later, the stars where the Sun had been during the eclipse. By comparing the two photographs, the deflection of light caused by the Sun’s gravity could be precisely measured. Einstein’ gravity theory predicted a deflection value of 1.75 arcseconds, and Newton’s gravity theory a value half that. The results were announced in November 1919 to a joint meeting of the Royal Society and the Royal Astronomical Society....

Scientists using NASA's Hubble Space Telescope have confirmed the presence of electrically-charged molecules in space shaped like soccer balls, shedding light on the mysterious contents of the interstellar medium (ISM) - the gas and dust that fills interstellar space. The molecules … are a form of carbon called "Buckminsterfullerene," also known as "Buckyballs," which consists of 60 carbon atoms (C60) arranged in a hollow sphere. C60 has been found in some rare cases on Earth in rocks and minerals, and can also turn up in high-temperature combustion soot. C60 has been seen in space before. However, this is the first...

Beams with highly structured angular momentum are said to have orbital angular momentum (OAM), and are called vortex beams. They appear as a helix surrounding a common center, and when they strike a flat surface, they appear as doughnut-shaped. In this new effort, the researchers were working with OAM beams when they found the light behaving in a way that had never been seen before. The experiments involved firing two lasers at a cloud of argon gas—doing so forced the beams to overlap, and they joined and were emitted as a single beam from the other side of the argon...

Researchers drew attention three years ago when they reported that a two-dimensional perovskite—a material with a specific crystal structure—composed of cesium, lead and bromine emitted a strong green light. Crystals that produce light on the green spectrum are desirable because green light, while valuable in itself, can also be relatively easily converted to other forms that emit blue or red light, making it especially important for optical applications ranging from light-emitting devices to sensitive diagnostic tools. But there was no agreement about how the crystal, CsPB2Br5, produced the green photoluminescence. Now, however, researchers from the United States, Mexico and China,...

The galaxy clusters Abell 0399 and Abell 0401 are some of the most massive objects in the universe. In a new study, researchers have discovered a 10-million-light-year-long bridge of radio waves (shown in blue in this composite image) linking them, and it’s doing crazy things to electrons. On the big roadmap of the universe, bustling clusters of galaxies are connected by long highways of plasma weaving around the wilderness of empty space. These interspace roadways are known as filaments, and they can stretch for hundreds of millions of light-years, populated only by dust, gas and busy electrons driving very close...

…[A] team of scientists working with a Harvard graduate student is for the first time applying deep learning — a powerful new version of the machine learning form of AI — to forecast sudden disruptions that can halt fusion reactions and damage the doughnut-shaped tokamaks that house the reactions. Unlike traditional software, which carries out prescribed instructions, deep learning learns from its mistakes. Accomplishing this seeming magic are neural networks, layers of interconnected nodes — mathematical algorithms — that are “parameterized,” or weighted by the program to shape the desired output. For any given input the nodes seek to produce...

Quantum mechanics’ core assumption is that on the smallest scales, atomic properties are quantized...For example, an electron can be in a lowest-energy state, but if you add a little more energy, it doesn’t slowly transition into the new higher-energy state. Rather, it unpredictably snaps into the new state. If you’re not looking at it, the atom can take on intermediate states—but these aren’t midway points. The atom would be in both states at the same time, and then once you observed it, it would immediately snap into one state or the other. The team’s artificial atom is an experimental apparatus...

After the first-ever image of a black hole confirmed theories posited by Einstein, it's the late scientist Stephen Hawking's turn to have parts of his life's work vindicated. In a paper published in Nature, scientists say that have verified the scientist's namesake theory, Hawking Radiation, which hypothesized that black holes emit radiation from their surfaces due to a mix of different factors regarding quantum physics and gravity. To verify the theory, scientists at the Technion-Israel Institute of Technology turned to what sounds like mad science: creating their own black hole.

For decades, physicists, engineers and mathematicians have failed to explain a remarkable phenomenon in fluid mechanics: the natural tendency of turbulence in fluids to move from disordered chaos to perfectly parallel patterns of oblique turbulent bands. This transition from a state of chaotic turbulence to a highly structured pattern was observed by many scientists, but never understood. For decades, physicists, engineers and mathematicians have failed to explain a remarkable phenomenon in fluid mechanics: the natural tendency of turbulence in fluids to move from disordered chaos to perfectly parallel patterns of oblique turbulent bands. This transition from a state of chaotic...

Some six months after the Great War of 1914-18 ended, Arthur Eddington travelled at the head of a team on a scientific expedition to the island of Principe off the coast of Equatorial Guinea in West Africa. He headed one of the two teams of astronomers assigned by a Joint Permanent Eclipse Committee of the Royal Society and the Royal Astronomical Society of Britain to observe and record photographically the full solar eclipse scheduled to take place on May 29, 1919. At the time under Portuguese rule, Principe was selected as one of the two sites – the other was...

Murray Gell-Mann, the Nobel-winning physicist who brought order to the universe by helping discover and classify subatomic particles, has died. He was 89. Gell-Mann died on Friday at his home in Santa Fe, New Mexico. His death was confirmed by the Santa Fe Institute, where he held the title of distinguished fellow, and the California Institute of Technology, where he taught for decades. The cause was not disclosed. Gell-Mann transformed physics by devising a method for sorting subatomic particles into simple groups of eight, based on electric charge, spin and other characteristics. He called his method the “eightfold way” after...