Researchers at Columbia University have created a superatomic material that’s being lauded as the “world’s best semiconductor.” Through a surprising twist of physics, it’s expected to allow processing (switching) speeds in the femtosecond scale. Here’s why it will most likely be a piece of the semiconductors puzzle, not its final shape.
Einstein’s fascination with light, considered quirky at the time, would lead him down the path to a brand new theory of physics.
Living half a century before Einstein, a Scotsman, James Clerk Maxwell, revealed a powerful unification and universalization of nature, taking the disparate sciences of electricity and magnetism and merging them into one communion. It was a titanic tour-de-force that compressed decades of tangled experimental results and hazy theoretical insights into a tidy set of four equations that govern a wealth of phenomena. And through Maxwell’s efforts was born a second great force of nature, electromagnetism, which describes, again in a mere four equations, everything from static shocks, the invisible power of magnets, the flow of electricity, and even radiation – that is, light – itself.
At the time Einstein’s fascination with electromagnetism was considered unfashionable. While electromagnetism is now a cornerstone of every young physicist’s education, in the early 20th century it was seen as nothing more than an interesting bit of theoretical physics, but really something that those more aligned in engineering should study deeply. Though Einstein was no engineer, as a youth his mind burned with a simple thought experiment: what would happen if you could ride a bicycle so quickly that you raced beside a beam of light? What would the light look like from the privileged perspective?
Isolate thin flakes that can be tuned to exhibit three important properties.
MIT is an acronym for the Massachusetts Institute of Technology. It is a prestigious private research university in Cambridge, Massachusetts that was founded in 1861. It is organized into five Schools: architecture and planning; engineering; humanities, arts, and social sciences; management; and science. MIT’s impact includes many scientific breakthroughs and technological advances. Their stated goal is to make a better world through education, research, and innovation.
In 1916, famed theoretical physicist Albert Einstein put the finishing touches on his Theory of General Relativity, a geometric theory for how gravity alters the curvature of spacetime. The revolutionary theory remains foundational to our models of how the Universe formed and evolved. One of the many things GR predicted was what is known as gravitational lenses, where objects with massive gravitational fields will distort and magnify light coming from more distant objects. Astronomers have used lenses to conduct deep-field observations and see farther into space.
In recent years, scientists like Claudio Maccone and Slava Turyshev have explored how using our Sun as a Solar Gravity Lens (SGL) could have tremendous applications for astronomy and the Search for Extratterstiral Intelligence (SETI). Two notable examples include studying exoplanets in extreme detail or creating an interstellar communication network (a “galactic internet”). In a recent paper, Turyshev proposes how advanced civilizations could use SGLs to transmit power from star to star – a possibility that could have significant implications in our search for technosignatures.
The preprint of Turyshev’s paper, “Gravitational lensing for interstellar power transmission,” recently appeared online and is being reviewed for publication. Slava G. Turyshev is a research scientist with the Structure of the Universe Research Group at NASA’s Jet Propulsion Laboratory. This group is engaged in a wide range of research topics associated with the evolution of the Universe from the Big Bang to the present day. This includes the formation of the first stars and galaxies, the role of Dark Matter and Dark Energy in the formation of large-scale cosmic structures, and the accelerating expansion of the cosmos Universe (respectively).
MIT physicists and colleagues have metaphorically turned graphite, or pencil lead, into gold by isolating five ultrathin flakes stacked in a specific order. The resulting material can then be tuned to exhibit three important properties never before seen in natural graphite.
“It is kind of like one-stop shopping,” says Long Ju, an assistant professor in the MIT Department of Physics and leader of the work, which is reported in the Nature Nanotechnology. “In this case, we never realized that all of these interesting things are embedded in graphite.”
Further, he says, “It is very rare to find materials that can host this many properties.”
Researchers in Germany and the U.S. have produced the first theoretical demonstration that the magnetic state of an atomically thin material, α-RuCl3, can be controlled solely by placing it into an optical cavity. Crucially, the cavity vacuum fluctuations alone are sufficient to change the material’s magnetic order from a zigzag antiferromagnet into a ferromagnet. The team’s work has been published in npj Computational Materials.
A recent theme in material physics research has been the use of intense laser light to modify the properties of magnetic materials. By carefully engineering the laser light’s properties, researchers have been able to drastically modify the electrical conductivity and optical properties of different materials.
However, this requires continuous stimulation by high-intensity lasers and is associated with some practical problems, mainly that it is difficult to stop the material from heating up. Researchers are therefore looking for ways to gain similar control over materials using light, but without employing intense lasers.
If you’ve ever drizzled honey on a piece of toast, you’ve noticed how the amber liquid folds and coils in on itself as it hits the toast. The same thing can happen with 3D and 4D printing if the print nozzle is too far from the printing substrate. Harvard scientists have taken a page from the innovative methods of abstract expressionist artist Jackson Pollock —aka the “splatter master”—to exploit the underlying physics rather than try to control it to significantly speed up the process, according to a new paper published in the journal Soft Matter. With the help of machine learning, the authors were able to decorate a cookie with chocolate syrup to demonstrate the viability of their new approach.
As reported previously, Pollock early on employed a “flying filament” or “flying catenary” technique before he perfected his dripping methods. The paint forms various viscous filaments that are thrown against a vertical canvas. The dripping technique involved laying a canvas flat on the floor and then pouring paint on top of it. Sometimes, he poured it directly from a can; sometimes he used a stick, knife, or brush; and sometimes he used a syringe. The artist usually “rhythmically” moved around the canvas as he worked. His style has long fascinated physicists, as evidenced by the controversy surrounding the question of whether or not Pollock’s paintings show evidence of fractal patterns.
Back in 2011, Harvard mathematician Lakshminarayanan Mahadevan collaborated with art historian Claude Cernuschi on an article for Physics Today examining Pollock’s use of a “coiling instability” in his paintings. The study mathematically describes how a viscous fluid folds onto itself like a coiling rope—just like pouring cold maple syrup on pancakes.
Astronomers are currently pushing the frontiers of astronomy. At this very moment, observatories like the James Webb Space Telescope (JWST) are visualizing the earliest stars and galaxies in the universe, which formed during a period known as the “Cosmic Dark Ages.” This period was previously inaccessible to telescopes because the universe was permeated by clouds of neutral hydrogen.
As a result, the only light is visible today as relic radiation from the Big Bang—the cosmic microwave background (CMB)—or as the 21 cm spectral line created by the reionization of hydrogen (aka the Hydrogen Line).
Now that the veil of the Dark Ages is being slowly pulled away, scientists are contemplating the next frontier in astronomy and cosmology by observing “primordial gravitational waves” created by the Big Bang. In recent news, it was announced that the National Science Foundation (NSF) had awarded $3.7 million to the University of Chicago, the first part of a grant that could reach up to $21.4 million. The purpose of this grant is to fund the development of next-generation telescopes that will map the CMB and the gravitational waves created in the immediate aftermath of the Big Bang.
This particular burst, called GRB 230307A, was likely created when two neutron stars — the incredibly dense remnants of stars after a supernova — merged in a galaxy about one billion light-years away. In addition to releasing the gamma-ray burst, the merger created a kilonova, a rare explosion that occurs when a neutron star merges with another neutron star or a black hole, according to a study published Wednesday in the journal Nature.
The Space Telescope Science Institute in Baltimore is the mission operations center for the telescope. It launched last in 2021 from French Guiana.
“There are only a mere handful of known kilonovas, and this is the first time we have been able to look at the aftermath of a kilonova with the James Webb Space Telescope,” said lead study author Andrew Levan, astrophysics professor at Radboud University in the Netherlands. Levan was also part of the team that made the first detection of a kilonova in 2013.
Dutch-born Christiaan Huygens is probably one of the most famous physicists you’ve never heard of. His work in the late 17th century straddled both the intangible and tangible realms of our Universe: the nature of light, and the mechanics of moving objects.
Among his many contributions, Huygens proposed a wave theory of light that would give rise to physical optics, which deals with the interference, diffraction, and polarization of light. He also invented the first pendulum clock; the most accurate timekeeper for almost 300 years, right through the Industrial Revolution.
Little has been made of the connections between these two seemingly disparate fields of optics and classical mechanics – until now.
