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Here’s what you’ll learn when you read this story: * Time travel is deterministic and locally free, a paper says—resolving an age-old paradox. * This follows research observing that the present is not changed by a time-traveling qubit. * It’s still not very nice to step on butterflies, though. ======================================================================= In a peer-reviewed paper, a scientist says he has mathematically proven the physical feasibility of a specific kind of time travel. The paper appears in Classical and Quantum Gravity. Germain Tobar and Fabio Costa, both of the University of Queensland at the time of the paper’s publication, worked together on...

We often imagine our galaxy as a serene, spinning disk of stars, a celestial carousel of light against the black velvet of space. This comforting image, however, is an illusion. From our tiny vantage point, embedded within one of its spiral arms, we are only now learning that the Milky Way is a place of profound and dynamic movement, a living entity that breathes and shudders on a scale almost impossible to comprehend. The latest revelation, born from the unparalleled data of the European Space Agency’s Gaia space telescope, is not just a wobble or a tilt, but a colossal,...

NATIONAL MOLE DAY We'll eliminate any visions of a burrowing creature celebration immediately; National Mole Day recognizes a special number in chemistry. Chemists and chemistry students mark the occasion each year on October 23rd. #NationalMoleDay More specifically, the celebrations take place between 6:02 AM and 6:02 PM. In the U.S., the time and date are written 6:02 10/23. The time and date are derived from Avogadro’s number. Avogadro's number is approximately 6.02×10^23. Hence, defining the number of particles (atoms or molecules) in one mole of a substance, one of the seven base SI units. A mole is a unit of...

Ireland has officially joined the European Organization for Nuclear Research (CERN) as an associate member state. CERN is an intergovernmental organization that operates the largest particle physics laboratory in the world on the Franco-Swiss border, just outside Geneva. The main focus of activity in CERN is the Large Hadron Collider (LHC), a 27-km (17-mile) underground ring in which protons are accelerated and collided into one another. Associate membership will allow Ireland’s researchers to participate in CERN’s scientific programs and will make Irish citizens eligible for staff positions and fellowships at CERN. …

Researchers make landmark advance in the quest to unlock virtually limitless clean energy from the same reaction that powers the stars On a former military airfield a few miles south of Oxford, a group of scientists are trying to bottle the sun. Not literally, of course — but their ambitions come close. Inside a four metre-tall, apple-shaped machine known as the Mega Amp Spherical Tokamak Upgrade (MAST-U), they are attempting to recreate, control and ultimately commercialise the fusion reactions that power the stars. In the past few weeks, they have made landmark progress. Fusion is physics’ grand prize, promising a...

Chatter Points * A new model suggests dark matter and dark energy may not be real entities, but effects of changing physical constants. * Galaxy rotation curves from seven galaxies fit the model using one key parameter: a “turn-off density.” * The approach also explains supernovae, galaxy clusters, and the cosmic microwave background without exotic matter. * Challenges remain: galaxies are complex, and no direct evidence yet shows that fundamental constants truly vary. ========================================================================== A physicist at the University of Ottawa has published research suggesting the universe’s most perplexing mysteries — dark matter and dark energy, which together supposedly account...

Thunderbird, the University of British Columbia’s benchtop-scale particle accelerator and electrochemical reactor. (Photo: UBC) ************************************************************************* Researchers at the University of British Columbia seeking the energy grail of cold fusion—alias lattice confinement fusion or low-energy nuclear reactions (LENR)— used electrochemistry to load extra deuterium ions into a metal lattice and found a “modest” performance boost of 15 percent, compared with experiments without the electrochemical loading technique, according to the university. While the experiment is benchtop scale, with more energy input than gained, it is the first time that deuterium–deuterium fusion has been demonstrated using the technique, according to UBC. The results...

A new study explains that time travel itself eventually leads to a reality without it. Is time travel truly possible? The prospect presents its fair share of paradoxes. Of course, there are famous logical examples, such as the Grandfather paradox, which explores what would happen if a time traveler killed their grandparent before their parent was conceived (an idea not so far removed from the plot of the sci-fi great Back to the Future). Other paradoxes are more concerned with mathematical or physical impossibilities within our current understanding of space-time—even though time travel is theoretically possible through phenomena like closed...

Earlier this year, astronomers watched a burst of high-energy light that kept roaring back for nearly a full day. Gamma-ray bursts (GRBs) are usually sorted into short and long events, and they generally last from milliseconds to a few minutes. In a new study, researchers describe a signal named GRB 250702B that fired three distinct times over a few hours, with soft X-rays flaring even earlier. The team also reported evidence that the source lies beyond our galaxy. Lead researchers Antonio Martin-Carrillo of University College Dublin (UCD) and Andrew J. Levan of Radboud University (RU) directed the effort. Their teams...

A rare cosmic configuration: An Einstein Cross with five points of light, instead of the usual four, has been discovered by scientists. (Credit: Nicolás Lira Turpaud (ALMA Observatory) & adapted from Cox et al. 2025) Brightest Glimpse Yet Of Dark Matter Comes From Rare Cosmic Lens In A Nutshell * Astronomers discovered HerS-3 forming a rare Einstein Cross with five images instead of four. * Computer models required a hidden dark matter halo of 1.6–10 trillion solar masses to explain the pattern. * The galaxy is magnified 17–19 times, revealing rapid star formation and high-speed gas outflows. * This is...

By splitting a single photon, scientists confirmed that angular momentum is always conserved — a billion-to-one experiment that reinforces the foundations of quantum physics. Credit: SciTechDaily.com ===================================================================== Physicists have, for the first time, shown that even a single photon obeys one of nature’s strictest rules: conservation of angular momentum. Achieved only once in a billion attempts, this needle-in-a-haystack success not only proves a cornerstone law of physics at the smallest scale but also opens a pathway to advanced quantum technologies, from entangled states to secure communication. Quantum-Level Confirmation of Angular Momentum Conservation Researchers at Tampere University, working with colleagues in...

Artist representation of CAPERS-LRD-z9, home to the earliest confirmed black hole. The supermassive black hole at its center is believed to be surrounded by a thick cloud of gas, giving the galaxy a distinctive red color. Credit: Erik Zumalt, The University of Texas at Austin ================================================================== Astronomers have discovered the most distant confirmed black hole, hidden inside a rare galaxy known as a “Little Red Dot.” Its enormous size and early existence challenge current theories about how galaxies and black holes formed in the young universe. A global team of astronomers, led by The University of Texas at Austin’s Cosmic...

Ultraviolet observations suggest that some heavy white dwarf mergers might be masquerading themselves. A white dwarf interacting with a red giant. Is this how this white dwarf formed? We do not know yet. Image credit: NASA, ESA, STScI, Ralf Crawford (STScI) Astronomers report the finding of a unique new object that doesn’t fit with categories that were only established in the last few years. They have observed an ultra-massive white dwarf with an outer layer of hydrogen and helium, 10 billion times thinner than other white dwarfs. This object is believed to be the product of a past merger event....

Astronomers at MIT, Columbia University, and elsewhere have used NASA’s James Webb Space Telescope to peer through the dust of nearby galaxies and into the aftermath of a black hole’s stellar feast. Credit: NRAO/AUI/NSF/NASA Unlike active galaxies that endlessly devour nearby matter, these black holes remain in slumber, stirring only momentarily to consume an unlucky passing star. Astronomers from MIT, Columbia University, and other institutions have used NASA’s James Webb Space Telescope (JWST) to look through thick layers of dust in nearby galaxies and examine the aftermath of black holes consuming stars. According to a new study published on July...

Scientists have long grappled with a fundamental question: what exactly is light?Is it a wave, flowing like ripples across water, or is it made up of tiny particles, like miniature paintballs zipping through space?This fundamental question was at the heart of the double-slit experiment, demonstrating light's dual nature.Just recently, physicists at MIT conducted an experiment using incredible atomic precision.Interestingly, it has definitively resolved a long-standing debate between quantum giants Albert Einstein and Niels Bohr about the elusive nature of light...Einstein believed he could devise an experiment to observe light's particle path and wave interference simultaneously.Bohr, leveraging the uncertainty principle, argued...

Sunspots, those mysterious dark patches on the Sun's surface, have been observed by astronomers for thousands of years. Yet, despite centuries of study, no one fully understood why these spots could remain stable for such extended periods. New research, however, has finally cracked the case, revealing that the secret lies in a delicate balance between the Sun's magnetic fields and the pressure of its plasma. Sunspots have been documented since at least 27 B.C., with Chinese astronomers recording the phenomenon long before Galileo peered at the Sun through his telescope. Some historical records even suggest that Greek philosopher Anaxagoras might...

While the study is intriguing, additional observations will be essential to verify or challenge its findings. Astudy analyzing JWST observations of the early universe has uncovered an intriguing mystery: most galaxies appear to be rotating in the same direction. This unexpected pattern, which defies current cosmological models, has led the study's authors to propose a bold possibility: that our universe might exist inside a black hole. The JWST has allowed astronomers to peer back further into the past than any other infrared or optical telescope, seeing infrared light that was emitted by distant galaxies just 300 million years after the...

The company claims it has cracked a scalable method to make stable gold from mercury. Ever since the discovery of alchemy, or since humans thought gold was a precious object, a worldwide quest to turn common elements into the yellow metal has been ongoing. Folklore and fables sing praises of humans who went on this quest and those who received such blessings. No such claims have yet stood the test of science, and this could change quite soon. An engineering firm from the United States – Marathon Fusion – has claimed that making gold from mercury is possible, and they...

Japanese researchers observed the transverse Thomson effect for the very first time, and it could groundbreaking. A Thermoelectric Seebeck module (w:en:Thermoelectric generator) manufactured by TECTEG MFR. Gerardtv ====================================================================== Researchers in Japan observed the transverse Thomson effect for the very first time, a thermoelectric phenomenon that allows the control of the direction of heating and cooling flows by changing the direction of the magnetic field. The scientific understanding of how heat and electricity interact stems from the 19th century. At the time, physicists only theorized the existence of a transverse Thomson effect, which refers to the direction in which an electric...

This visualization explores a subset of toe bean-reminiscent structures within a section of the Cat's Paw Nebula, a massive, local star-forming region located approximately 4,000 light-years away in the constellation Scorpius.This image by NASA's James Webb Space Telescope in near-infrared light was released in honor of the telescope's third science operations anniversary. Since it began science operations in July 2022, Webb's observations of our universe have wowed scientists and the public alike.Glide into the lower left toe bean, moving past many small yellow stars along the way, where filaments of gas and dust frame the cavernous area. The region's nebulous...