Tag

Physics

All articles tagged with #physics

science5 days ago•5 min saved

Cosmic Fate Rewritten: Could the Universe End in a Big Crunch

A Cornell-led analysis proposes the expansion of the universe could be temporary and eventually reverse if the cosmological constant is negative, driven by an ultralight axion field. The model places the universe’s total lifespan at about 33.3 billion years, with a slow crunch starting in roughly 11 billion years and final collapse about 8 billion years later (around 19–20 billion years from now). If dark energy’s behavior continues to deviate from a true constant, this Big Crunch scenario could hold; upcoming surveys and missions (Euclid, Rubin Observatory, SPHEREx) are expected to refine measurements and test the idea.

via Indian Defence Review|

#big-crunch #cosmology #dark-energy

space8 days ago•58 min saved

Thirty Cosmos Facts That Will Blow Your Mind

BuzzFeed’s list of 30 mind-blowing space facts spans the cosmos—from the observable universe’s staggering scale (about one septillion stars) and a universe dominated by dark energy and dark matter to eye-opening specifics like Venus’s day lasting longer than its year, Saturn’s ultra-low density (it would float in water), Olympus Mons dwarfing Earth’s tallest mountain, and the Moon’s regolith preserving footprints for up to 100 million years. It also covers neutron stars’ immense density, interstellar visitors like Oumuamua and Borisov, a giant reservoir of water 12 billion light-years away, blue sunsets on Mars, and even the Sun’s hypothetical roar in space.

via BuzzFeed|

#astronomy #cosmology #physics

science9 days ago•5 min saved

Scientists Photograph Light in Motion, Revealing Terrell Rotation at Near-Light Speeds

Researchers from the University of Vienna used pulsed lasers and ultrafast cameras to photograph light moving at near-light speeds, recreating the Terrell–Penrose rotation and showing how objects would appear rotated rather than squashed; by capturing slices of light and stitching them, they slowed light to about 2 m/s to visualize the motion, with implications for relativity studies, particle physics, and astrophysics.

via The Daily Galaxy|

#high-speed-imaging #light-speed-photography #physics

physics15 days ago•9 min saved

Decoding Quantum Chaos with a Single Scramblon

A combined experiment/theory study using solid-state NMR on a powder of adamantane demonstrates that quantum chaos in a many-body system can be captured by a single scramblon mode. By applying scramblon theory to disentangle intrinsic chaotic scrambling from imperfections in time reversal, researchers extract a quantum Lyapunov exponent and a universal decay parameter, supporting a universal, simple description of chaotic dynamics that could bridge tabletop quantum experiments with holographic gravity concepts.

via American Physical Society|

#lyapunov-exponent #nmr #otoc

physics17 days ago•83 min saved

Graphene bilayers reveal a reversible superfluid-to-supersolid transition in excitons

Physicists using two closely spaced graphene layers, a strong magnetic field, and ultracold temperatures observed bilayer excitons transition from a superfluid to an insulating, lattice-like state (interpreted as a supersolid) and then revert back to a superfluid, marking the first reported reversible superfluid-to-supersolid transition in this system in a Nature study led by Cory Dean and colleagues.

via Live Science|

#bilayer-graphene #excitons #physics

science23 days ago•11 min saved

Could Our Cosmos Be a Giant Computer Simulation?

The article surveys the simulation hypothesis—the idea that our universe might be a highly realistic computer simulation—by tracing Nick Bostrom’s argument that advanced beings could run trillions of simulations. It notes that, while the logic remains compelling for some (and figures like Neil deGrasse Tyson have called the odds roughly 50-50), there is no empirical proof, and critics argue that computing such vast simulations may be infeasible or that apparent glitches don’t prove we’re in a simulation. The discussion also connects physics and cosmology to the idea, including limits like the finite observable horizon and the idea of reality as potentially ‘pixelated’ at small scales."}{

via The Conversation|

#cosmology #philosophy #physics

technology28 days ago•12 min saved

Masers Rise Again: From Microwave Marvel to Room-Temperature Quantum Possibility

Masers are the microwave cousins of lasers that power cryogenic amplifiers for deep-space signals, provide precise timekeeping with hydrogen and cesium clocks, and appear in natural astrophysical sources; advances in new materials could enable room-temperature masers and even chip-scale devices for quantum computing, signaling a potential revival beyond their historical role.

via Hackaday|

#maser #microwave #physics

science1 month ago•33 min saved

Memories in the vacuum: are we living as Boltzmann Brains?

Physicists propose the Boltzmann Brain hypothesis: given enough time, random fluctuations could create a brain with all your memories, making our recollections potentially illusory. In a paper in Entropy, lead author David Wolpert and co-authors Carlo Rovelli and Jordan Scharnhorst argue this is a plausible consequence of physics, though there’s no rigorous way to prove or disprove it. They connect the idea to thermodynamics and argue that grounding our sense of time still rests on the Big Bang, concluding we shouldn’t panic, but the notion challenges the reliability of memory as a reflection of past reality.

via Daily Mail|

#big-bang #boltzmann-brain #entropy

physics1 month ago•16 min saved

Emergent Topology Arises in Quantum-Critical CeRu4Sn6

Researchers at TU Wien report that the quantum material CeRu4Sn6 enters a quantum-critical regime at ultra-low temperatures where electrons lose their particle-like character, yet the system hosts an emergent topological semimetal state. They observed a spontaneous (anomalous) Hall effect without an external magnetic field, linking quantum fluctuations to topology and suggesting that topological properties can arise even when the conventional particle-picture fails. The work also points to a generalized, emergent view of topology and proposes focusing on quantum-critical materials to discover new topological phases.

via SciTechDaily|

#ceru4sn6 #condensed-matter-physics #emergent-topological-semimetal

science1 month ago•36 min saved

Thermodynamics Reimagined: A New Framework for Non‑Equilibrium Energy

Researchers at West Virginia University have expanded the first law of thermodynamics to describe energy conversion in non‑equilibrium systems by incorporating additional quantitative descriptors beyond density and temperature, enabling a more complete account of energy flow in complex substances such as plasmas, chemistry, circuitry, and quantum systems; the breakthrough could reshape how scientists model energetic processes across multiple fields.

via Yahoo|

#energy #non-equilibrium #physics

physics-and-mathematics1 month ago•54 min saved

Sticky Space? New Idea Says the Vacuum Could Be a Viscous Fluid Shaping the Cosmos

A new arXiv preprint proposes space may have bulk viscosity, effectively making the vacuum a viscous medium with spatial phonons that could slow cosmic expansion and better align DESI observations with reality. If true, this viscous-space model would challenge the standard Lambda-CDM cosmology and the cosmological constant, potentially redefining our understanding of dark energy. However, the idea is unreviewed and data-driven, with questions about whether viscosity is fundamental or a measurement artifact; upcoming data from Euclid and further DESI analyses will be crucial to test this hypothesis.

via Live Science|

#bulk-viscosity #cosmology #dark-energy

science1 month ago•5 min saved

Ghostly Vacuum Signals Could Redefine Gravity

A theoretical study suggests Cherenkov radiation in empty space could arise from a negative-energy ghost instability, uniting two seemingly different phenomena and offering a potential window into modified gravity; if true, the vacuum would have structure and stored energy, but the idea remains purely theoretical with no practical detection method yet.

via ScienceAlert|

#cherenkov-radiation #cosmology #gravity

science1 month ago•4 min saved

Is Reality Made of Equations? The Minimalist Math Universe

Part 2 explores Max Tegmark’s Mathematical Universe Hypothesis, arguing that the universe may be fundamentally mathematical and that human concepts are “baggage” to be stripped away. By applying Occam’s razor, the piece suggests reality reduces to pure math—relationships and structures—so a final theory of everything could be a single mathematical description that explains all of reality, potentially eliminating constants, dimensions, and the need for a separate physics framework.

via Universe Today|

#cosmology #mathematical-universe-hypothesis #max-tegmark

science1 month ago•3 min saved

Japanese Sensor Could Unlock Dark Matter Secrets

Physicists at the University of Tokyo and Chuo University have developed a highly sensitive quantum sensor array that could potentially detect and track dark matter by measuring its movement through space, offering a more general and sensitive approach than traditional methods, though it remains at the theoretical stage.

via The Daily Galaxy|

#dark-matter #particle-detection #physics

science1 month ago•3 min saved

China Unveils Record-Breaking Hypergravity Machine to Compress Space and Time

China has developed a new hypergravity centrifuge, CHIEF 1900, capable of generating accelerations of 1,900 g·tonne, to study materials and fundamental physics under extreme conditions, with applications in civil engineering and scientific research, though such forces are lethal to humans.

via IFLScience|

#centrifuge #engineering #hypergravity