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New evidence suggests Einstein’s cosmic constant may be wrong

Dark energy may be evolving—hinting that the universe’s ultimate destiny could be far stranger than we ever imagined. Astronomers are rethinking one of cosmology’s biggest mysteries: dark energy. New findings show that evolving dark energy models, tied to ultra-light axion particles, may better fit the universe’s expansion history than Einstein’s constant model. The results suggest dark energy’s density could be slowly declining, altering the fate of the cosmos and fueling excitement that we may be witnessing the universe’s next great revelation.

Dark energy, the mysterious force thought to drive the universe’s accelerating expansion, remains one of the deepest puzzles in modern physics. For years, the leading explanation has been that this energy is constant – an unchanging property of empty space responsible for cosmic acceleration. But recent evidence has scientists rethinking that assumption.

Last year, results from the Dark Energy Survey (DES) and the Dark Energy Spectroscopic Instrument (DESI) caught the attention of cosmologists by suggesting that dark energy might not be fixed after all. “This would be our first indication that dark energy is not the cosmological constant introduced by Einstein over 100 years ago but a new, dynamical phenomenon,” explained Josh Frieman, Professor Emeritus of Astronomy and Astrophysics.

Universe’s expansion ‘is now slowing, not speeding up’

The universe’s expansion may actually have started to slow rather than accelerating at an ever-increasing rate as previously thought, a new study suggests.

“Remarkable” findings published today in Monthly Notices of the Royal Astronomical Society cast doubt on the long-standing theory that a mysterious force known as ‘dark energy’ is driving distant galaxies away increasingly faster.

Instead, they show no evidence of an accelerating universe.

A Mathematician’s Model Brings Science Fiction’s Wormholes Closer to Reality

Could a tunnel through space and time—long a dream of science fiction—ever exist in theory? According to Arya Dutta, a Ph.D. student in Mathematics at the Katz School, the answer might be yes, at least on paper.

Accepted for publication in the International Journal of Geometric Methods in Modern Physics, Dutta’s study, “Thin-shell Wormhole with a Background Kalb–Ramond Field,” explored a mathematical model of a wormhole—a hypothetical shortcut through spacetime that could, in theory, connect two distant regions of the universe. “A wormhole allows faster-than-light travel or even time travel,” said Dutta. “It hasn’t been observed yet, but theoretical research has advanced a lot.”

‘Impossible’ merger of two massive black holes explained

In 2023, astronomers detected a huge collision. Two unprecedentedly massive black holes had crashed an estimated 7 billion light-years away. The enormous masses and extreme spins of the black holes puzzled astronomers. Black holes like these were not supposed to exist.

Now, astronomers with the Flatiron Institute’s Center for Computational Astrophysics (CCA) and their colleagues have figured out just how these black holes may have formed and collided. The astronomers’ comprehensive simulations—which follow the system from the lives of the parent stars through to their ultimate death—uncovered the missing piece that previous studies had overlooked: magnetic fields.

“No one has considered these systems the way we did; previously, astronomers just took a shortcut and neglected the magnetic fields,” says Ore Gottlieb, astrophysicist at the CCA and lead author of the new study on the work published in The Astrophysical Journal Letters. “But once you consider magnetic fields, you can actually explain the origins of this unique event.”

What if the CMB Isn’t Actually Cosmic? — Dr. Patrick Vanraes, DemystifySci #380

The universe hums a low, steady note…or so we were told. Dr. Patrick Vanraes, a plasma physicist from the University of Antwerp, joins us in that quiet static, where light and truth blur at the edges. We talk of cosmic beginnings, instrument design, of warmth beneath the skies, of radio echoes mistaken for the birth of everything. In that hum, between curiosity and doubt, the cosmos seems to ask who’s really paying attention.

CORRECTION NOTE: Dr. Robitaille wishes it to be known that when he says \.

A long, bumpy caterpillar-like wormhole may connect two black holes

For obvious reasons, we do not know what the inside of a black hole looks like. But thanks to theoretical physics, we can ask what the inside should look like if Einstein’s theory of gravity and the rules of quantum mechanics are both true. A new study published in the journal Physical Review Letters has done exactly this by concentrating on two black holes that are deeply entangled (linked together by quantum rules).

The research by scientists from the U.S. and Argentina theoretically mapped the shared inner space between the two objects—the wormhole connecting them. They found that for a typical, messy entangled pair, the interior isn’t the smooth tunnel of science fiction.

Instead, it’s a long, lumpy structure they called the “Einstein-Rosen caterpillar.” It’s named after the Einstein-Rosen Bridge, the mathematical structure that connects two regions of spacetime, and “caterpillar” because of its bumpy, segmented shape. This discovery is a significant step toward proving that the bizarre rules of quantum mechanics can control the shape of spacetime inside a black hole.

Most Powerful Black-Hole Flare Ever Recorded Shone Like 10 Trillion Suns

In a flare of light that traveled for 10 billion years to reach us, astronomers have identified the most powerful and most distant blaze of energy ever recorded from a black hole, an eruption whose peak shone with the power of 10 trillion Suns.

The cause of this colossal event, says a team led by astrophysicist Matthew Graham of Caltech, was likely a supermassive black hole 500 million times the mass of the Sun devouring an unlucky star that flew a little too close to the powerful gravity well at the center of a distant galaxy. These black hole feasts are known as tidal disruption events (TDEs).

“The energetics show this object is very far away and very bright,” Graham says. “This is unlike any AGN [active galactic nucleus] we’ve ever seen.”

Nonlocality-enabled photonic analogies of parallel spaces, wormholes and multiple realities

Multiverse and wormholes are experimentally elusive due to dimensional constraints. Here, authors use nonlocal artificial materials and deep learning to emulate photonic parallel spaces, realizing invisible zero-index tunnels and independent optical devices coexisting at the same physical location.

Stellar Giants Forged the Chemical Diversity of Ancient Clusters

“Extremely massive stars may have played a key role in the formation of the first galaxies,” said Dr. Paolo Padoan.


How did the extremely massive stars (EMS) in the early universe help form the oldest star clusters? This is what a recent study published in the Monthly Notices of the Royal Astronomical Society hopes to address as an international team of scientists investigated the role that EMS played in not only forming globular clusters (GCs), but how the latter were responsible for forming the first black holes. This study has the potential to help scientists better understand the conditions of the early universe and what this could mean to better understanding our existence.

For the study, the researchers presented a new computational model to help explain how EMS contributed to GC formation with bodies celestial objects being between 1,000 to 10,000 times as massive as our Sun and containing hundreds of thousands to millions of stars, respectively. Given the massive sizes and short lifetimes of EMS, they go supernova when they die, and the new model postulates they become black holes while releasing massive amounts of chemical and hydrogen that mixes with surrounding gas and dust, resulting in the formation of GCs. Additionally, data obtained from NASA’s James Webb Space Telescope (JWST) discovered nitrogen-rich galaxies had chemical signatures obtained from GCs.

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