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In the far future, we could reveal detailed views of distant worlds by turning our home star into a gravitational lens Diagram showing a conceptual imaging technique that uses the sun’s gravitational field to magnify light from exoplanets. This would allow for highly advanced reconstructions of what exoplanets look like. We now know of more than 5,000 exoplanets beyond the solar system. What we really understand about each of these worlds, though, is barely anything at all. Most of them have been seen only indirectly from their shadows as they cross in front of the stars they orbit. The...

In all of physical law, there’s arguably no principle more sacrosanct than the second law of thermodynamics — the notion that entropy, a measure of disorder, will always stay the same or increase. “If someone points out to you that your pet theory of the universe is in disagreement with Maxwell’s equations — then so much the worse for Maxwell’s equations,” wrote the British astrophysicist Arthur Eddington in his 1928 book The Nature of the Physical World. “If it is found to be contradicted by observation — well, these experimentalists do bungle things sometimes. But if your theory is found...

Ever since astronomers found that Earth and the Solar System are not unique in the cosmos, humanity has dreamed of the day when we might explore nearby stars and settle extrasolar planets. Unfortunately, the laws of physics impose strict limitations on how fast things can travel in our Universe, otherwise known as Einstein’s General Theory of Relativity. Per this theory, the speed of light is constant and absolute, and objects approaching it will experience an increase in their inertial mass (thereby requiring more mass to accelerate further). While no object can ever reach or exceed the speed of light, there...

Bell’s theorem states that no theory that incorporates local “hidden” variables can ever reproduce the correlations between measurement outcomes that quantum mechanics predicts. A similar result occurs in the theory of causal inference, where quantum systems likewise defy the rules of classical causal reasoning. The idea behind the causal inference approach is that while a statistical correlation between two variables can arise due to a direct causal relationship between them, the correlation may also contain the contribution of a hidden common cause. [T]he researchers use a causal model (see image) in which the statistics of variable A influence those of...

ASTROPHYSICS A team of University of Copenhagen astrophysicists has arrived at a major result regarding star populations beyond the Milky Way. The result could change our understanding of a wide range of astronomical phenomena, including the formation of black holes, supernovae and why galaxies die. The Andromeda galaxy, our Milky Way's closest neighbor, is the most distant object in the sky that you can see with your unaided eye. For as long as humans have studied the heavens, how stars look in distant galaxies has been a mystery. In a study published today in The Astrophysical Journal, a team of...

[A]n unseen ‘mirror world’ of particles that interacts with our world only via gravity might be the key to solving a major puzzle in cosmology today – the Hubble constant problem. The Hubble constant is the current rate of expansion of the universe. Predictions for this rate — from cosmology’s standard model — are significantly slower than the rate found by our most precise local measurements. This discrepancy is one that many cosmologists have been attempting to solve by changing our current cosmological model. The challenge is to do so without ruining the agreement between standard model predictions and many...

Since 2003, the black hole at the center of the Perseus galaxy cluster has been associated with sound. This is because astronomers discovered that pressure waves sent out by the black hole caused ripples in the cluster's hot gas that could be translated into a note—one that humans cannot hear, some 57 octaves below middle C. Now a new sonification brings more notes to this black hole sound machine. This new sonification—that is, the translation of astronomical data into sound—is being released for NASA's Black Hole Week this year. In some ways, this sonification is unlike any other done before...

In two weeks' time, the European Southern Observatory (ESO) is going to present the world with new information about our Milky Way. It's anyone's guess what the announcement will be, but based on what we know of their recent efforts, there's reason to get excited – the results being presented are from the Event Horizon Telescope (EHT) project, which was responsible for producing the first-ever image of a black hole in 2019. For years now the EHT project has been studying the heart of our home galaxy, the Milky Way, which is most likely home to a supermassive black hole...

Associate professor Mazhar Ali and his research group at TU Delft have discovered one-way superconductivity without magnetic fields, something that was thought to be impossible ever since its discovery in 1911 – up till now. The discovery, published in Nature, makes use of 2D quantum materials and paves the way towards superconducting computing. Superconductors can make electronics hundreds of times faster, all with zero energy loss. Ali: “If the 20th century was the century of semi-conductors, the 21st can become the century of the superconductor.” During the 20th century many scientists, including Nobel Prize winners, have puzzled over the nature...

Does time exist? The answer to this question may seem obvious: Of course it does! Just look at a calendar or a clock. But developments in physics suggest the non-existence of time is an open possibility, and one that we should take seriously. How can that be, and what would it mean? It'll take a little while to explain, but don't worry: Even if time doesn't exist, our lives will go on as usual. A crisis in physics Physics is in crisis. For the past century or so, we have explained the Universe with two wildly successful physical theories: general...

Subatomic particles paint pictures of inner worlds of pyramids, volcanoes and more illustration of muon particles raining down on the Great Pyramid of Giza - An invisible rain of the subatomic particles called muons pierces structures on Earth’s surface, including the Great Pyramid of Giza. Those muons can help map out the chambers within the pyramid and have even revealed an unexplained hidden void. Inside Egypt’s Great Pyramid of Giza lies a mysterious cavity, its void unseen by any living human, its surface untouched by modern hands. But luckily, scientists are no longer limited by human senses. To feel out...

Two teams of researchers working independently have shown the viability of using neutral atoms to create quantum circuits—both have published outlines of their work in the journal Nature. One of the groups, with members from the University of Wisconsin, Madison, ColdQuanta and Riverlane, successfully ran an algorithm on a cold atom quantum computer for the first time. The second group, with members from Harvard, MIT, QuEra Computing Inc., the University of Innsbruck and the Austrian Academy of Sciences, showed that it was possible to build a quantum processor based on coherent transport of entangled atom arrays. Hannah Williams, with Durham...

[T]he teams at CERN were able to make a number of updates and improvements to the particle accelerator to support new, next-generation science during the scheduled shutdown. As the most powerful accelerator in the world, the LHC can generate hundreds of millions of particle collisions every second. Although the LHC has led to new physics research throughout both of its previous, successful runs, teams at CERN hope to push their explorations with the new upgrades implemented during the shutdown. Included in these improvements, CERN has increased the power of the LHC's injectors, which feed the beams of accelerated particles into...

Cuprous oxide crystal. (University of St Andrews) One of the ways we can fully realize the potential of quantum computers is by basing them on both light and matter – this way, information can be stored and processed, but also travel at the speed of light. Scientists have just taken a step closer to this goal, by successfully producing the largest hybrid particles of light and matter ever created. These quasiparticles, known as Rydberg polaritons, were made with the help of a piece of stone containing cuprous oxide (Cu2O) crystals from an ancient deposit in Namibia, one of the few...

Artist’s impression of GNz7q (ESA/Hubble, N. Bartmann) A first-of-its-kind 'missing link' object detected in the early Universe may solve the mystery of the oldest supermassive black holes in existence, scientists say. The discovery of GNz7q, a black hole dating back to just 750 million years after the Big Bang, aligns with theoretical predictions of what an 'ancestor' to supermassive black holes might look like – and while it's something we've never seen before, there could be many more like it. "It's unlikely that discovering GNz7q … was just 'dumb luck'," says astronomer Gabriel Brammer from the University of Copenhagen in...

Scientists just outside Chicago have found that the mass of a sub-atomic particle is not what it should be. The measurement is the first conclusive experimental result that is at odds with one of the most important and successful theories of modern physics. The team has found that the particle, known as a W boson, is more massive than the theories predicted. The scientists at the Fermilab Collider Detector (CDF) in Illinois have found only a tiny difference in the mass of the W Boson compared with what the theory says it should be - just 0.1%. But if confirmed...

The Fermilab Collider Detector obtained a result that could transform the current theory of physics Scientists just outside Chicago have found that the mass of a sub-atomic particle is not what it should be. The measurement is the first conclusive experimental result that is at odds with one of the most important and successful theories of modern physics. The team has found that the particle, known as a W boson, is more massive than the theories predicted. The result has been described as "shocking" by Prof David Toback, who is the project co-spokesperson. The discovery could lead to the development...

Scientists have detected a strange new type of high-frequency wave on the sun's surface, and the waves are moving three times faster than scientists thought was possible. The acoustic waves, called high-frequency retrograde (HFR) vorticity waves, were spotted rippling backward through the sun's plasma in the opposite direction of its rotation. The previously unknown type of wave was described in a study published March 24 in the journal Nature Astronomy. Scientists can't see into the sun's fiery depths, so they often measure the acoustic waves that move across its surface and bounce back toward its core to infer what's going...

The further we move away from a heat source, the cooler the air gets... the surface of the Sun starts at 6000 degC, but over a short distance of only a few hundred kilometers, it suddenly heats up to more than a million degrees, becoming its atmosphere, or corona...The popular theories are based on heating caused by turbulence, and heating caused by a type of magnetic wave called ion cyclotron waves.“Both, however, have some problem – turbulence struggles to explain why Hydrogen, Helium and Oxygen in the gas become as hot as they do, while electrons remain surprisingly cold; while...

<p>At the heart of every black hole sits a problem. As they sizzle away into nothingness over the eons, they take with them a small piece of the Universe. Which, quite frankly, just isn't in the rule book.</p><p>It's a paradox the late Stephen Hawking left us with as a part of his revolutionary work on these monstrous objects, inspiring researchers to tinker with potential solutions for the better part of half a century.</p>