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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...

...Scientists have been keeping a close watch on those changes, both to ensure there’s nothing unexplainable by our current understanding, but also to compare 3I/ATLAS to both previous interstellar visitors as well as comets in our own solar system. A recent paper from European researchers describes how the changes in a particular material ratio in 3I/ATLAS’ coma fit with our current understanding of cometary geology.That ratio is the nickel to iron (Ni/FE) abundance ratio. It has been measured for two decades, including on twenty in-system comets as well as 2I/Borisov, the last known interstellar visitor our solar system had. However,...

A photograph of a black graphite disk floating above a stack of three, round magnets. (Credit: Adrian Skov (OIST)) Study shows how perfect magnetic symmetry can cancel energy loss. In A Nutshell Researchers at OIST built a 10-millimeter graphite disk that levitates and spins above a magnetic array inside a vacuum chamber. By arranging magnets in perfect circular symmetry, the setup cancels the eddy currents that normally slow conductors moving through magnetic fields. Even at one-billionth of Earth’s air pressure, the disk kept spinning with almost no slowdown; only tiny tilts or material imperfections created measurable friction. This ultra-stable, contact-free...

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...

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...

Space can surprise even those who spend their lives studying it. People often think of our solar system as just a few planets and a bunch of empty space. Yet new observations suggest we have been living inside a hot, less dense region, and that there may even be a strange cosmic channel connecting us to distant stars. After years of careful mapping, a new analysis reveals what appears to be a channel of hot, low-density plasma stretching out from our solar system toward distant constellations. Astronomers from the Max Planck Institute recently confirmed it using data from the eRosita...

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...

The Ig Nobel Prize honors research that first makes people laugh, then makes them think. Its 35th award ceremony possibly also makes people hungry: ISTA physicist Fabrizio Olmeda and colleagues researched the secret of a perfect cacio e pepe pasta sauce. They received the popular award for their findings on Thursday evening in Boston, U.S. .....

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...

It looked like the Sun was heading toward a historic lull in activity. That trend flipped in 2008, according to new research. The Sun has become increasingly active since 2008, a new NASA study shows. Solar activity is known to fluctuate in cycles of 11 years, but there are longer-term variations that can last decades. Case in point: Since the 1980s, the amount of solar activity had been steadily decreasing all the way up to 2008, when solar activity was the weakest on record. At that point, scientists expected the Sun to be entering a period of historically low activity....

Virginia Tech engineers have designed an “ice slingshot” that can propel frozen disks of water across a flat, grooved surface without any external force. Previous experiments have demonstrated a similar forceless propulsion of dry ice on a layer of vapor. However, the novel ice slingshot produces a similar motion without harmful CO2. The Virginia Tech team suggests their approach could lead to the development of energy generation devices or micro-transportation systems and potentially offer unique de-icing approaches. In an email to The Debrief, Associate Professor Jonathan Boreyko from Virginia Tech’s School of Mechanical Engineering explained the process relies on a...

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....