Category Archives: Physics

Cosmic Halo

10 April 2025 By in Physics, Science, Space Tags: , , , , , , , , , Leave a comment

Galactic halos, consisting of a spherical envelope of dark matter along with sparsely scattered stars, globular clusters, and gas, typically surround most spiral galaxies. Current research is investigating the possibility that some halos may exist solely of dark matter. Discovering halos without stellar matter carries profound implications for our understanding of the universe’s structure, galaxy formation processes, and the conditions required for star formation. More importantly, such a discovery would provide a unique laboratory to study dark matter in isolation, free from interference of normal matter. However, new findings suggest that starless halos may be even rarer than previously thought. This scarcity makes detecting such halos particularly challenging, as they are unlikely to be associated with observable galaxies.

Ethan Nadler, of the University of California San Diego, has demonstrated that molecular hydrogen requires significantly less mass for star formation compared to atomic hydrogen. His research shows that molecular hydrogen can cool sufficiently for gravity to initiate star formation at lower mass thresholds. Specifically, while past studies indicated that dark matter halos need between 100 million to 1 billion solar masses of atomic hydrogen to begin star formation, Nadler has revealed that molecular hydrogen can achieve the same result with as little as 10 million solar masses—a reduction by a factor of 10 to 100. While dark matter halos can theoretically form with masses as low as 10⁻⁶ solar masses, depending on the nature of dark matter, those capable of influencing galaxy formation typically require at least 10⁶ solar masses to enable star formation, further highlighting the challenge of finding starless halos. Detecting these small, starless halos would require identifying subtle perturbations in gravitational fields, a difficult task that may yield little if such halos are as rare as current models suggest.

Source: …Galaxy Formation Threshold, Nadler, AAS, April 2025. Graphic: Dark Matter Halo Simulation by Cosmo0. Public Domain.

Geo Anomalies

3 April 2025 By in Physics, Science Tags: , , , , , , , , , Leave a comment

NASA has identified the South Atlantic Magnetic Anomaly (SAA) as a region off the coast of South America, where Earth’s magnetic field is significantly weaker. This weakening reduces magnetic shielding, exposing satellites and spacecraft to higher levels of radiation and posing a risk to their operation. Understanding the causes and implications of the SAA is essential for addressing these LEO challenges.

One hypothesis suggests that irregularities at the core-mantle boundary disrupt the geodynamo, the mechanism generating Earth’s magnetic field. The anomaly’s alignment with submarine volcanic features hints at possible links between mantle-crust interactions and magnetic disturbances. Additionally, a hotspot near the Mid-Atlantic Ridge corresponds to a geomagnetic intensity minimum at the core-mantle boundary, implying that thermal and compositional anomalies in the mantle may affect convection in the molten outer core, creating localized variations in the magnetic field.

Further research using subsurface imaging will help in uncovering the internal processes shaping Earth’s magnetic field and enhancing our understanding of the planet’s protective geodynamo.also assist in predicting magnetic anomalies and their effect on LEO space flight in the future.

Source: NASA. Graphic. Core Geomagnetic Anomaly, NASA.

Fate of the Universe

27 March 2025 By in Physics, Science, Space Tags: , , , , , , , , , , Leave a comment

Astronomers once observed exploding stars (supernovae) and found the universe expanding, driven by a mysterious force called dark energy. This led to the standard cosmological model of the late 1990s, Lambda-CDM, where “Lambda” represents dark energy, assumed constant, and “Cold Dark Matter” (CDM) explains unseen mass shaping cosmic structure. Evidence for CDM includes steady star rotation speeds in galaxies, cosmic microwave background fluctuations, galaxy clustering, and light bending by gravity. Though successful, Lambda-CDM has faced ongoing scrutiny almost from inception of the theory.

Enter the Dark Energy Spectroscopic Instrument (DESI) at Kitt Peak National Observatory in Arizona. With 5,000 robotic fiber-optic sensors, DESI captures light from galaxies and quasars, mapping the universe’s expansion history. A new study, analyzing three years of DESI data, 15 million objects, with plans for 50 million, combines it with cosmic microwave background radiation, supernovae, and weak gravitational lensing data. Fitting all this into Lambda-CDM with a constant dark energy revealed cracks in the model. But if dark energy weakens over time, a “dynamical dark energy“, the model aligns better.

By observing objects up to 11 billion years away, DESI peers deep into cosmic history. Researchers found hints that dark energy’s strength may have peaked around 7 billion years ago, then started weakening, challenging its fixed nature in Lambda-CDM. While not certain, this could rival the 1990s discovery of accelerated expansion, potentially demanding a new model.

The universe’s fate depends on dark energy versus matter. It’s been accelerating, but a weakening dark energy might slow it down, halt it, or, if gravity overtakes sufficiently, trigger a “Big Crunch.” New data from DESI, Europe’s Euclid, NASA’s Nancy Grace Roman, and Chile’s Vera Rubin Observatory could clarify this within five years, possibly nailing dark energy’s role.

Source: “Dark Energy Seems to Be Changing, Rattling Our View of Universe” by Rey and Lawler, Phys.org, March 2025. Graphic: DESI Collaboration Photo of Galaxies.

White Holes, Black Holes, and the Cosmic Cycle

20 March 2025 By in Physics, Science, Space Tags: , , , , , , Leave a comment

White holes, theoretical counterparts to black holes, might be two sides of a cosmic coin. Black holes devour matter with relentless gravity; white holes expel it, hurling energy, particles, and possibly time into the universe. Both stem from Einstein’s general relativity, which predicts black holes, proven by solid evidence, while white holes remain elusive, perhaps lurking beyond our Earthly senses. 

To see their link, rethink black holes’ strangest feature and flaw: the singularity. General relativity paints it as a point where spacetime crushes so tight that physics breaks, a bug, not a feature. Exotic matter, with odd traits like negative energy, was once the fix. But the University of Barcelona’s Pablo Bueno and team ditched it, tweaking gravity with higher-curvature corrections to erase singularities. This needs extra dimensions beyond our four, turning black holes from traps into dynamic zones. 

The University of Sheffield adds a twist: the event horizon isn’t sharp. Quantum gravity blurs it into a fuzzy gateway where spacetime bends, not breaks. In 4D, black holes are sinkholes, matter vanishes. In higher dimensions, it slips through, heading elsewhere. Sheffield’s take ties this to dark energy, the universe’s expansion driver. Here, it’s the power plant: quantum fluctuations, fueled by dark energy, replace the singularity with a bounce, flipping spacetime to a white hole. 

Enter white holes, Janus-like transitions, Roman god of gates and duality. Black holes vacuum everything; white holes, linked via higher dimensions, spit it out, maybe far off. Picture Sagittarius A*, the Milky Way’s core black hole, channeling matter 25,000 light-years to the Orion Nebula’s arm. Unseen, white holes might hide in dimensions we can’t touch. 

This hints at a cosmic cycle, like Earth’s water cycle: evaporate, rain, repeat. Black holes swallow, dark energy and quantum gravity bounce it through higher dimensions, and white holes release it back. Barcelona and Sheffield suggest no endpoints, just a recycling of cosmic raw materials across realms we’re barely capable of understanding.

Source: Black Hole Singularity, Gielen and Menendez-Pidal, University of Sheffield, 2025. Regular Black Holes…by Bueno, P. et al, Physics Letter B, February 2025. Graphic: Black Hole Rendering.

Cosmic Gold Rush

6 March 2025 By in Physics, Science Tags: , , , , , , 1 Comment

Ultra-high-energy cosmic rays (UHECRs) are the universe’s most energetic particles, with energies exceeding 100 quintillion electronvolts (100 EeV)—far beyond anything we can replicate on Earth. First observed over 60 years ago, these particles have puzzled scientists with their immense power and a curious pattern: their energy correlates closely with their electric charge. But where do they come from?

A new theory by physicist Glennys Farrar from New York University offers an answer. She proposes that UHECRs originate in binary neutron star (BNS) mergers—explosive collisions that form a black hole. These events unleash powerful jets of material, acting as cosmic particle accelerators that boost particles to unimaginable energies. The idea links UHECRs’ narrow energy range and charge correlation to a range of combined neutron star mass sufficient to form a black hole.

The theory suggests that the highest-energy UHECRs—those above 100 EeV—could be heavy elements like gold, platinum, or uranium, forged in extreme cosmic events such as supernovae or neutron star collapses (stars can only create elements up to iron through fusion). By tying UHECRs to BNS mergers, Farrar’s work could reveal how precious elements form and deepen our understanding of cosmic cataclysms.

Source: Binary Neutron Star Mergers… by Glennys R. Farrar, Physical Review Letters, 28 February 2025. Graphic: Two Neutron Stars Merging by Universe Today.

Gravity and Vanilla Black Holes

27 February 2025 By in Physics, Science, Space Tags: , , , , , , , , , , , , , Leave a comment

Einstein’s theory of general relativity, which includes gravity, predicts that black holes have a tricky feature: a singularity. This is a point where space and time are squeezed so tightly that the laws of physics break down—think of it as a cosmic “error message.” To fix this, scientists often turn to exotic matter—hypothetical substances with bizarre properties like negative energy—to smooth things out. However, a team from the University of Barcelona, led by Pablo Bueno, found an alternative. They didn’t need exotic matter at all. Instead, they tweaked Einstein’s gravity by adding an infinite series of extra “rules” (higher-curvature corrections) to the math.

Their solution works in spacetimes with more than four dimensions—beyond our usual height, width, depth, and time. In these higher-dimensional worlds, black holes can exist without singularities. This “smooths out” black holes, making them less mysterious and more like regular objects in spacetime—no weird stuff required.

The presence of extra dimensions doesn’t just fix singularities—it can also change how black holes behave. In higher-dimensional spacetimes, black holes might have different event horizon shapes (the boundary beyond which nothing escapes) or other structural quirks. The Barcelona team’s work shows that these altered properties emerge naturally from gravity in more than four dimensions, offering a fresh perspective on these cosmic giants.

Thinking outside the box, is it possible that these extra dimensions link black holes to “a reality outside regular spacetime,” like wormholes (tunnels through spacetime), braneworlds (parallel universes on higher-dimensional “membranes”), or even gateways to white holes (theoretical opposites of black holes that spit stuff out)? Theories like string theory and braneworld scenarios suggest that extra dimensions might allow such connections. For example, a wormhole could theoretically bridge two distant points in our universe—or even lead to a completely different universe.

While the math of higher dimensions opens the door to these possibilities, it’s all conjecture. The Barcelona team’s work is a major step forward in understanding black holes in higher dimensions, but it doesn’t directly prove connections to other realities.

Source: Grok 3. Regular Black Holes… by Bueno, P. et al., Physics Letter B, February 2025. Graphic: Black Hole Rendering, iStock licensed.

Put Your Lights On

24 January 2025 By in Physics Tags: , , , , , , , , , , , , , , , Leave a comment

A distant galaxy at the edge of the universe and the beginning of time has revealed a remarkable discovery by Yale researchers. They have identified a variable quasar that rapidly brightens as its astrophysical jets periodically align with the position of Earth.

The researchers believe that this quasar, and others like it, played a significant role in bringing light into the early dark universe, alongside massive early stars which preceded the quasars.

Quasars are supermassive black holes at the centers of early galaxies, spinning at relativistic speeds. These early galaxies contained substantial unincorporated material, primordial gas clouds akin to present-day nebulae, which were easily captured by the black hole’s gravity. Near the event horizon of the black hole, this matter is caught in a ‘turbulent’ vortex, creating massive astrophysical jets. These jets, partially composed of ionized plasmas, are expelled at relativistic speeds, extending up to hundreds of light-years from the black hole and perpendicular to its event horizon. As the ionized hydrogen plasmas capture electrons from the neutral hydrogen in the early universe, photons are released, contributing to the illumination of the cosmos.

Thomas Connor, an astronomer at the Chandra X-Ray Center and co-corresponding author of the study, states, “[This] epoch of reionization is considered the end of the universe’s dark ages.”

Trivia: The song Put Your Lights On was written by Erik Schrody (Everlast) and performed with Santana on his 1999 album Supernatural. He wrote the song while recovering from a heart attack, pondering the hope that exists in life.

Source: This Quasar May Have Helped Turn the Lights on… by Shelton, Yale, 2025. Graphic: Black Hole Outflows from Centaurus A, ESO, 2009.

Plasma Jets

17 January 2025 By in Physics Tags: , , , , , , , , , Leave a comment

In a galaxy far, far away within the Draco (Dragon) constellation, an international team has, for the first time, observed plasma jets forming in real time and shooting out at relativistic speeds, perpendicular to the plane of a black hole’s event horizon. Plasma jets, composed of ionized matter, are a subset of astrophysical jets—energetic, narrow beams of matter and radiation ejected from various objects, primarily black holes, along their axis of rotation.

These plasma jets were observed in the Milky Way’s gravitationally captured satellite, the Draco Dwarf Galaxy, located 270 million light-years from Earth. The Draco Dwarf Galaxy is home to a black hole that apparently has a white dwarf star companion. A likely scenario is that the white dwarf was once a companion to a much larger star that evolved faster, went supernova, and collapsed into a black hole. Today, the black hole is possibly cannibalizing material from the white dwarf, potentially leading to the plasma jets observed by researchers.

Source: Astronomers observe real-time formation of black hole jets by UMBC, 2025. Graphic: Black Hole Outflows from Centaurus A, ESO, 2009.

Fractional Excitons

10 January 2025 By in Physics Tags: , , , , , , , Leave a comment

Physicists at Brown University have recently observed a new class of quantum particles called fractional excitons.

Excitons consist of an electron and an electron hole (a quasiparticle, a concept, representing the absence of an electron where one should exist). They allow for energy transfer in a lattice, such as in a transistor. Applying voltage to a transistor influences the movement of electrons and holes through the material. Simplified, this movement can turn the current flow on and off, forming a logic gate.

Despite being composed of fermions, excitons exhibit bosonic behavior and follow bosonic statistics. Fractional excitons, however, show behaviors that don’t fully align with either fermions or bosons. This suggests they belong to a new class of particles with previously unobserved quantum properties.

The researchers speculate that these fractional excitons may lead to advances in quantum computing.

Source: Excitons, Zhang et al, Nature, 2025. Graphic: Quasiparticles, Demin Liu, Brown University 2025.

Mass–No Mass

13 December 2024 By in Physics Tags: , , , , , , , , , Leave a comment

A team of researchers from Penn State and Columbia University has recently observed a quasi-particle that is massless when moving in one direction but acquires mass when moving in a different direction. This quasi-particle, known as a semi-Dirac fermion, was captured by the team inside a ZrSiS crystal and was first theorized 16 years ago. The scientists observed that when the particle travels in one direction at the speed of light, it remains massless. However, when it is forced to change direction, it slows down for the ‘turn’ and gains mass.

This property relates to Einstein’s most famous equation, E=mc², which states that energy and mass are interchangeable, connected by the speed of light squared. According to Einstein’s Theory of Special Relativity, mass traveling at the speed of light would have infinite mass and require infinite energy to maintain its speed, which is impossible. Therefore, only massless particles can travel at the speed of light.

Relativistic effects also come into play when objects approach and attain the speed of light. As an object with mass moves faster, time dilation and length contraction effects become significant. At the speed of light, time would effectively stop for the object, and distances would shrink to zero. These extreme conditions are not physically achievable for objects with mass.

Source: ScienceDaily by Adrienne Berard, 2024. Semi-Dirac Fermions in a Topological Metal. Physical Review X, Shao, et al, 2024.