Latest news with #PhysicalReviewD
Yahoo
15 hours ago
- Science
- Yahoo
'A bundle of microscopic tornadoes' may have given the universe its structure
When you buy through links on our articles, Future and its syndication partners may earn a commission. The universe's invisible dark matter might swirl into spinning clumps laced with countless tiny vortices, new theoretical work suggests. The findings, published May 30 in the journal Physical Review D, offer a fresh perspective on the strange behavior of "ultralight" dark matter — a hypothetical substance made of extremely light elementary particles. In the new study, physicists explored what happens when a dark matter halo rotates — a natural expectation for real galaxies, which typically spin as they evolve. Based on their theoretical modeling and detailed simulations, the authors found that this exotic material could behave like a superfluid, forming stable, rotating cores threaded with vortex lattices much like those seen in laboratory experiments. Unlike the standard view of dark matter as a cloud of heavy, sluggish particles with no internal structure, the new research focuses on dark matter made of particles lighter than a millionth of an electron's mass. These particles may not float passively in space; if they interact slightly with one another through a repulsive force, they can behave more like a quantum fluid. That fluid-like behavior allows the formation of "solitons" — compact, coherent structures where gravity's pull inward is balanced by an outward pressure from self-interactions. "Solitons are classical solutions of the equations of motion," Philippe Brax, a theoretical physicist at Université Paris-Saclay and co-author of the study, told Live Science. "They correspond to hydrostatic equilibria where the attractive gravitational force is balanced by the repulsive particle self-interaction, somewhat like the Sun, which is also in hydrostatic equilibrium." These solitons could range from the size of stars to entire galaxies, depending on the unknown mass of the dark matter particle. In larger cases, they could help explain why the centers of galaxies appear less densely packed with dark matter than predicted — a long-standing issue in cosmology. The researchers simulated what happens when clouds of this unusual dark matter rotate. The result was surprising: Instead of spinning smoothly like a hurricane or a solid sphere, the solitons developed an internal lattice of microscopic vortices. "When the initial conditions are such that the dark matter cloud rotates, the end result is a rotating soliton at the center of the collapsed halo," said study co-author Patrick Valageas, also of the Université Paris-Saclay. "This soliton shows an oblate shape aligned with the initial rotation axis, and displays a solid-body rotation supported by quantized vortices." These vortices aren't like swirling winds or whirlpools in water. Rather, they resemble the quantized vortex lines that appear in superfluids like liquid helium, where the fluid rotates not as a whole but through an array of discrete spinning threads. At the center of each vortex, the dark matter density drops to zero, and together, the vortices align into a regular, lattice-like pattern. "Our simulations show that these vortex lines are aligned with the total angular momentum and follow circular orbits inside the soliton," Valageas said. "The rotation is not like a smooth wind but more like a bundle of microscopic tornadoes arranged in a crystal pattern." One intriguing idea the researchers raised is whether these tiny vortex structures have implications on much larger scales. In particular, they speculated that some vortex lines might extend beyond a single halo, connecting galaxies through the vast filaments of the cosmic web — the gigantic tendrils of dark matter that shape the universe's large-scale structure. "At this stage, the idea that some of these vortex lines could join different halos through the filaments of the cosmic web is a hypothesis," Brax noted. If true, it could mean that quantum effects in dark matter subtly influence how galaxies align and move within these colossal threads. Detecting such vortex structures would be challenging. Because dark matter doesn't emit or absorb light, scientists can only infer its presence from its gravitational influence on visible matter like stars and gas. Still, there may be ways to glimpse their effects. "These vortices are associated with troughs in the dark matter density," Brax said. "As such, they imprint characteristic features in the gravitational potential, which may influence the orbits of stars or gas clouds in galaxies like the Milky Way." related stories —Dark matter may have its own 'invisible' periodic table of elements —Scientists may have finally found where the 'missing half' of the universe's matter is hiding —Scientists are one step closer to knowing the mass of ghostly neutrinos — possibly paving the way to new physics In more speculative scenarios, if dark matter interacts even weakly with ordinary matter or light, the vortices might leave more direct fingerprints — but for now, that remains an open question. The team plans to investigate whether the predicted vortex lattices can be detected through astronomical observations and whether they truly connect to the cosmic filaments that stretch across space. For now, these ghostly whirlpools remain invisible — but as theory and technology advance, scientists may find that the cosmos is not just filled with unseen matter but woven with patterns of spinning quantum threads.
Yahoo
13-06-2025
- Science
- Yahoo
A Scientist Thinks the Universe Bounced Out of a Black Hole
Here's what you'll learn when you read this story: A new hypothesis from physicists at the University of Portsmouth in the U.K. challenges the long-standing Big Bang Theory as the ultimate origin of the universe. This new 'Black Hole Universe' hypothesis, suggests that our universe possibly 'bounced' from the formation of larger black hole in another parent universe. While intriguing, the Big Bang Theory is the undisputed cosmological champ for a reason, so it'll take lots of rigorous experiments to confirm its theoretical conclusions. Throughout human history, there has been no greater question than 'where do we come from?' This existential curiosity has spawned entire religions, philosophies, and (more recently) serious scientific inquiry. Amazingly, as science and technology have progressed over the past century, we've begun to actually answer that age-old question. Thanks to groundbreaking discoveries in the 20th century—not the least of which was the accidental discovery of the cosmic microwave background in the 1960s—we now know that the universe most likely formed from a rapid expansion of matter known formally as the Big Bang. But just because the Big Bang is our best answer for the beginning of everything, that doesn't mean it's the only one. In the early years, the main competitor to Big Bang Cosmology was the Steady State Universe (though the discovery of the CMB largely put that idea to rest). But in recent years, new alternatives have emerged to challenge the Big Bang's cosmological supremacy. One of the latest in this contrarian family is detailed in a new paper published in the journal Physical Review D, in which physicists from the University of Portsmouth in the U.K. theorize that maybe our universe formed within an interior black hole of a larger parent universe. Yeah, let's dig into it. Comparisons between black holes and the cosmology of our universe make some sense—after all, both contain singularities of a sort and horizons beyond which we can't hope to glimpse. However, this new theory, which is called the 'Black Hole Universe,' suggests that our black hole-generated universe is just one step in a cosmological cycle driven by gravity and quantum mechanics. 'The Big Bang model begins with a point of infinite density where the laws of physics break down. This is a deep theoretical problem that suggests the beginning of the Universe is not fully understood,' Enrique Gaztanaga, lead author of the study from the University of Portsmouth, said in a press statement. 'We've questioned that model and tackled questions from a different angle—by looking inward instead of outward. Instead of starting with an expanding Universe and asking how it began, we considered what happens when an overdensity of matter collapses under gravity.' The genesis of this theory and others like it stems from the fact that we simply don't know what goes on the heart of black hole. And because knowledge (like nature) abhors a vacuum, scientists begin crafting hypotheses in an attempt to understand this unknown. In Gaztanaga and his team's case, they've shown that a gravitational collapse doesn't necessarily end in a singularity, but can instead 'bounce' into a new expansion phase. 'Crucially, this bounce occurs entirely within the framework of general relativity, combined with the basic principles of quantum mechanics,' Gaztanaga's team said in a press statement. 'We now have a fully worked-out solution that shows the bounce is not only possible—it's inevitable under the right conditions. One of the strengths of this model is that it makes predictions that can be thoroughly tested.' As a science coordinator on the ESA mission Analysis of Resolved Remnants of Accreted galaxies as a Key Instrument for Halo Surveys, or ARRAKIHS (a true master-class in science acronym-ing), Gaztanaga hopes to use the instrument's ability to analyze ultra-low surface brightness structures in the outskirts of galaxies to see if data points to a 'Black Hole Universe' or the undisputed scientific champ, the Big Bang. Presenting alternative ideas to long-standing theories is a key function of the scientific method, as it rigorously tests what we think we know from new angles. Even if ARRAKIHS confirms our Big Bang suspicions (as it most likely will), this alternative hypothesis still take us one step closer to truly understanding a question that's followed our species for hundreds of thousands of years. You Might Also Like The Do's and Don'ts of Using Painter's Tape The Best Portable BBQ Grills for Cooking Anywhere Can a Smart Watch Prolong Your Life?
Mint
12-06-2025
- Science
- Mint
Are we inside a black hole? New study challenges the Big Bang theory: ‘We are not special'
A new study by UK scientists has questioned the famous Big Bang theory. It suggests the universe may not have started from a single explosion. The research, published in Physical Review D by scientists from the University of Portsmouth, puts forward a bold new idea. It says our universe exists inside a black hole. The team believes the universe was born from a huge gravitational collapse that formed a black hole. This theory, called the 'Black Hole Universe', goes against the older idea that the universe came from a point of infinite density. Instead, the new theory says the matter inside the black hole got extremely compressed. Then, it bounced outward like a spring. This bounce is believed to have led to the universe we see today. The idea suggests that the universe was not created from nothing. But, it is part of a continuous cycle of collapse and rebirth. The study challenges long-held views of cosmic beginnings. According to Professor Enrique Gaztanaga, when matter collapses due to gravity, it doesn't always end in a point of infinite density. Instead, it can become very dense and then bounce back, creating a new, expanding universe. According to the theory, our universe's edge is the black hole's event horizon. It is a boundary that blocks us from seeing what lies beyond. Unlike the Big Bang theory, this model combines general relativity and quantum physics. Quantum laws say matter cannot be compressed forever. "We are not special. We are not witnessing the birth of everything from nothing, but rather the continuation of a cosmic cycle - one shaped by gravity, quantum mechanics, and the deep interconnections between them," GB News quoted Prof Gaztanaga as saying. New images from the James Webb Space Telescope show more early galaxies spinning one way than the other. This odd pattern suggests the universe may have been born spinning. This is believed to be a sign it could have formed inside a black hole. Experts say this idea, called black hole cosmology, might also explain the mystery of dark matter and supermassive black holes. The Big Bang Theory says that our whole universe began from one tiny point nearly 14 billion years ago. Then, like a sudden explosion, this tiny point burst and started expanding in all directions. At that time, there were no people, Earth, or sky: just energy and tiny particles flying around. Slowly, over lakhs and crores of years, stars, galaxies and planets like our Earth began to form.
BreakingNews.ie
10-06-2025
- Science
- BreakingNews.ie
Universe was not formed in big bang but ‘bounced' out of black hole
The Universe may not have started with the Big Bang, but instead 'bounced' out of a massive black hole formed within a larger 'parent' universe, according to a new scientific paper. Professor Enrique Gaztanaga, from the University of Portsmouth's Institute of Cosmology and Gravitation, said that the current Big Bang theory was problematic as the laws of physics 'broke down' when used to explain it. Advertisement His new explanation, published in the journal Physical Review D, suggests that the Universe was formed as a result of a gravitational collapse in a larger universe which generated a massive black hole leading to a rebound or 'bounce' causing our universe to emerge. Professor Gaztanaga said: 'The Big Bang model begins with a point of infinite density where the laws of physics break down. 'This is a deep theoretical problem that suggests the beginning of the Universe is not fully understood. 'We've questioned that model and tackled questions from a different angle – by looking inward instead of outward. Advertisement 'Instead of starting with an expanding universe and asking how it began, we considered what happens when an over-density of matter collapses under gravity.' Prof Gaztanaga explained that the theory developed by his team of researchers worked within the principles of quantum mechanics and the model could be tested scientifically. He said: 'We've shown that gravitational collapse does not have to end in a singularity and found that a collapsing cloud of matter can reach a high-density state and then bounce, rebounding outward into a new expanding phase. 'Crucially, this bounce occurs entirely within the framework of general relativity, combined with the basic principles of quantum mechanics. What emerges on the other side of the bounce is a universe remarkably like our own. Advertisement 'Even more surprisingly, the rebound naturally produces a phase of accelerated expansion driven not by a hypothetical field but by the physics of the bounce itself. 'We now have a fully worked-out solution that shows the bounce is not only possible – it's inevitable under the right conditions. 'One of the strengths of this model is that it makes predictions that can be thoroughly tested. And what's more this new model has also revealed that the Universe is slightly curved, like the surface of the Earth.' He added: 'Furthermore, it could also shed new light on other deep mysteries in our understanding of the early universe such as the origin of supermassive black holes, the nature of dark matter, or the formation and evolution of galaxies.' Advertisement Prof Gaztanaga, who is the science co-ordinator for the ARRAKIHS ESA space mission, said that the four wide-angle telescopes on the satellite could help confirm the theory through its ability to detect ultra-low surface brightness structures in the outskirts of galaxies which he explained were essential for studying how galaxies grow and evolve.
The Journal
10-06-2025
- Science
- The Journal
The universe may not have originated with the Big Bang, new study reveals
THE UNIVERSE MAY not have started with the Big Bang, but instead 'bounced' out of a massive black hole formed within a larger 'parent' universe, according to a new scientific paper. Professor Enrique Gaztanaga, from the University of Portsmouth's Institute of Cosmology and Gravitation, said that the current Big Bang theory was problematic as the laws of physics 'broke down' when used to explain it. His new explanation, published in the journal Physical Review D, suggests that the Universe was formed as a result of a gravitational collapse in a larger universe which generated a massive black hole leading to a rebound or 'bounce' causing our universe to emerge. Professor Gaztanaga said: 'The Big Bang model begins with a point of infinite density where the laws of physics break down. 'This is a deep theoretical problem that suggests the beginning of the Universe is not fully understood. 'We've questioned that model and tackled questions from a different angle – by looking inward instead of outward. 'Instead of starting with an expanding universe and asking how it began, we considered what happens when an over-density of matter collapses under gravity.' Advertisement Prof Gaztanaga explained that the theory developed by his team of researchers worked within the principles of quantum mechanics and the model could be tested scientifically. He said: 'We've shown that gravitational collapse does not have to end in a singularity and found that a collapsing cloud of matter can reach a high-density state and then bounce, rebounding outward into a new expanding phase. 'Crucially, this bounce occurs entirely within the framework of general relativity, combined with the basic principles of quantum mechanics. What emerges on the other side of the bounce is a universe remarkably like our own. 'Even more surprisingly, the rebound naturally produces a phase of accelerated expansion driven not by a hypothetical field but by the physics of the bounce itself. 'We now have a fully worked-out solution that shows the bounce is not only possible – it's inevitable under the right conditions. 'One of the strengths of this model is that it makes predictions that can be thoroughly tested. And what's more, this new model has also revealed that the Universe is slightly curved, like the surface of the Earth.' He added: 'Furthermore, it could also shed new light on other deep mysteries in our understanding of the early universe, such as the origin of supermassive black holes, the nature of dark matter, or the formation and evolution of galaxies.' Professor Gaztanaga, who is the science co-ordinator for the ARRAKIHS ESA space mission, said that the four wide-angle telescopes on the satellite could help confirm the theory through its ability to detect ultra-low surface brightness structures in the outskirts of galaxies, which he explained were essential for studying how galaxies grow and evolve.
