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Dismantling the belief in a static universe, Edwin Hubble's revolutionary observations in the 1920s laid the groundwork for our understanding of a continually expanding cosmos. However, we must seek to reconcile this theory with observations that are consistent with a non-expanding universe, writes Tim Anderson. You have been taught that the universe began with a Big Bang, a hot, dense period about 13.8 billion years ago. And the reason we believe this to be true is because the universe is expanding and, therefore, was smaller in the past. The Cosmic Microwave Background is the smoking gun for the Big Bang,...

A team of researchers claims to have created the first materials that conduct electricity perfectly at room temperature and ambient pressure, but many physicists are highly sceptical. Speaking to New Scientist, Hyun-Tak Kim at the College of William & Mary in Virginia says he will support anyone trying to replicate his team’s work. Superconductors are materials through which electricity can move without encountering any resistance, and so would significantly cut down the energy costs of electronics. But for over a century, researchers have been unable to make them work except under extreme conditions like very low temperatures and remarkably high...

If you've been following my channel for a really long time, you might remember that some years ago I made a video about whether faster-than-light travel is possible. I was trying to explain why the arguments saying it's impossible are inconclusive and we shouldn't throw out the possibility too quickly, but I'm afraid I didn't make my case very well. This video is a second attempt. Hopefully this time it'll come across more clearly!I Think Faster Than Light Travel is Possible. Here's Why. | 23:46Sabine Hossenfelder | 943K subscribers | 1,569,919 views | April 8, 2023

Mathematician Per Enflo, who solved a huge chunk of the 'invariant subspaces problem' decades ago, may have just finished his work.This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights. Nathan Brownlowe, Senior Lecturer in the School of Mathematics and Statistics at the University of Sydney. Two weeks ago, a modest-looking paper was uploaded to the arXiv preprint server with the unassuming title "On the invariant subspace problem in Hilbert spaces". The paper is just 13 pages long and its list of references contains only a single entry. The paper...

A new measurement confirms the subatomic particle’s spherical shape to a record level of exactness, physicists report in the July 7 Science. That near-perfect roundness deepens the mystery behind how the universe came to be filled with matter as opposed to its counterpart, antimatter. Any asymmetry in the electron’s shape, namely the distribution of the particle’s electric charge, would point to a related asymmetry in the laws of nature, one that could explain this feature of the cosmos. The measurement — of a property known in physicist-speak as the electric dipole moment of the electron — is twice as precise...

"Palatial Twistor Theory; in order to describe a general, Lorentzian, globally hyper-bolic 4-dimensional space-time in twistor terms, we appear to be driven to a holomorphic non-commutative twistor-geometry, even for Classical space-time."

Five Theories About the Universe to Blow Your Mind | 15:02Sideprojects | 733K subscribers | 1,568,801 views | November 8, 2022

This isn't the first time astronomers have measured M92's age, but previous estimates relied on just one synthetic collection of stars. Comparing thousands of them reduced the uncertainty introduced by the assumptions baked into each one. The new technique reduced the uncertainty of the cluster age by about 50 percent, Ying says. The team found the cluster is 13.8 billion years old, give or take 750 million years. That's strikingly close to the best estimate of the age of the universe: a smidge over 13.8 billion years, plus or minus 24 million years, according to the Planck satellite's measurement of...

In a Bose-Einstein condensate, the bosons within a material have such low energy that they all occupy the same state, acting as a single particle. This allows quantum properties to be seen on a macroscopic scale. A Bose-Einstein condensate was created in a lab for the first time in 1995, at a temperature of a mere 170 nanokelvin.Now, let’s look at what happens in a typical leaf during photosynthesis.Plants need three basic ingredients to make their own food — carbon dioxide, water, and light. A pigment called chlorophyll absorbs energy from light at red and blue wavelengths. It reflects light...

Developing commercial fusion energy requires scientists to understand sustained processes that have never before existed on Earth. But with so many unknowns, how do we make sure we're designing a device that can successfully harness fusion power?We can fill gaps in our understanding using computational tools like algorithms and data simulations to knit together experimental data and theory, which allows us to optimize fusion device designs before they're built, saving much time and resources.Currently, classical supercomputers are used to run simulations of plasma physics and fusion energy scenarios, but to address the many design and operating challenges that still remain,...

Researchers at Microsoft say they have created elusive quasiparticles called Majorana zero modes – but scientists outside the company are sceptical Microsoft researchers have made a controversial claim that they have seen evidence of an elusive particle that could solve some of the biggest headaches in quantum computing, but some experts are questioning the discovery. Quantum computers process information using quantum bits, or qubits, but current iterations can be prone to error. “What the field needs is a new kind of qubit,” says Chetan Nayak at Microsoft Quantum. He and his colleagues say they have taken a significant step...

Originally built to speed up calculations, a machine-learning system is now making shocking progress at the frontiers of experimental quantum physicsQuantum physicist Mario Krenn remembers sitting in a café in Vienna in early 2016, poring over computer printouts, trying to make sense of what MELVIN had found. MELVIN was a machine-learning algorithm Krenn had built, a kind of artificial intelligence. Its job was to mix and match the building blocks of standard quantum experiments and find solutions to new problems. And it did find many interesting ones. But there was one that made no sense. “The first thing I thought...

In the most massive test to date, physicists have probed a major paradox in quantum mechanics and found it still holds even for clouds of hundreds of atoms.Using two entangled Bose-Einstein condensates, each consisting of 700 atoms, a team of physicists co-led by Paolo Colciaghi and Yifan Li of the University of Basel in Switzerland has shown that the Einstein-Podolsky-Rosen (EPR) paradox scales up.The researchers say this has important implications for quantum metrology – the study of measuring things under quantum theory...One of the tools we use to close one of the gaps is quantum mechanics, a theory that arose...

In November 2021, the Parker Solar Probe skimmed within a more-than-hair-singeing 8.5 million kilometers (5.3 million miles) of the Sun, a feat enabling it to detect the fine structure of the solar wind as it gusted tons of charged particles out into the Solar System through a hole in the Sun's corona, or atmosphere.The probe's readings give us the closest look yet at how the fast solar wind is generated, suggesting that a specific type of magnetic reconnection is what drives this powerful force of nature, according to a team of physicists led by Stuart Bale of the University of...

Concept Black Hole Illustration A team of researchers has affirmed Stephen Hawking’s prediction about the evaporation of black holes via Hawking radiation, though they’ve provided a crucial modification. According to their research, the event horizon (the boundary beyond which nothing can escape a black hole’s gravitational pull) is not as important as previously believed in producing Hawking radiation. Instead, gravity and the curvature of spacetime play significant roles in this process. This insight extends the scope of Hawking radiation to all large objects in the universe, implying that, over a sufficiently long period, everything in the universe could evaporate. Research...

Supramolecular assemblies of six rubidium and one iron atom. Scanning tunneling microscopy revealed the clear signal of the one iron atom. (Ajayi et al., Nature, 2023) ***************************************************************************** Atoms may not have bones, but we still want to know how they are put together. These tiny particles are the basis on which all normal matter is built (including our bones), and understanding them helps us understand the larger Universe. We currently use high-energy X-ray light to help us understand atoms and molecules and how they're arranged, catching diffracted beams to reconstruct their configurations in crystal form. Now, scientists have used X-rays...

The Pinwheel Galaxy has a new bright spot. ... an animation showing a bright star explosion appearing in a spiral galaxy Long Island, New York-based astrophotographer Steven Bellavia produced this composite animation of the Pinwheel Galaxy using an image taken on April 21 and comparing it to another image taken on May 21, which clearly shows the supernova appearing. (Image credit: Steven Bellavia) Astronomers and amateurs alike are excited about a new star explosion visible in small telescopes. The new supernova popped into visibility on May 19 in the Pinwheel Galaxy, (also designated as Messier 101, or M101). The galaxy...

Red giant star Betelgeuse. (ALMA - ESO/NAOJ/NRAO, E/O'Gorman/P.Kervella) Since what has come to be known as the Great Dimming that took place in the latter half of 2019 and early 2020, the red giant star Betelgeuse just will not stop with the wackiness. The dying star's regular cycles of brightness fluctuation have changed, and now Betelgeuse has grown uncharacteristically bright. At the time of writing, it was sitting at 142 percent of its normal brightness. It's been fluctuating back and forth on a small scale but on a steady upward trend for months and hit a recent peak of 156...

Over the past few decades, scientists have made incredible progress in understanding and manipulating biological systems at increasingly small scales, from protein folding to genetic engineering. And yet, the extent to which quantum effects influence living systems remains barely understood...Quantum effects are phenomena that occur between atoms and molecules that can't be explained by classical physics...Instead, tiny objects behave according to a different set of laws known as quantum mechanics.

Einstein's general theory of relativity predicts the existence of black holes, formed when giant stars collapse. But that same theory predicts that their centers are singularities, which are points of infinite density. Since we know that infinite densities cannot actually happen in the universe, we take this as a sign that Einstein's theory is incomplete. But after nearly a century of searching for extensions, we have not yet confirmed a better theory of gravity.But we do have candidates, including string theory. In string theory all the particles of the universe are actually microscopic vibrating loops of string. In order to...