'The universe has thrown us a curveball': Largest-ever map of space reveals we might have gotten dark energy totally wrong
Astronomers studying the largest-ever map of the cosmos have found hints that our best understanding of the universe is due a major rewrite.
The analysis, which looked at nearly 15 million galaxies and quasars spanning 11 billion years of cosmic time, found that dark energy — the presumed-to-be constant force driving the accelerating expansion of our universe — could be weakening.
Or at least this is what the data, collected by the Dark Energy Spectroscopic Instrument (DESI), suggest when combined with information taken from star explosions, the cosmic microwave background and weak gravitational lensing.
If the findings hold up, it means that one of the most mysterious forces controlling the fate of our universe is even weirder than first thought — and that something is very wrong with our current model of the cosmos. The researchers' findings were published in multiple papers on the preprint server arXiv and presented March 19 at the American Physical Society's Global Physics Summit in Anaheim, California, so they have not yet been peer-reviewed.
"It's true that the DESI results alone are consistent with the simplest explanation for dark energy, which would be an unchanging cosmological constant," co-author David Schlegel, a DESI project scientist at the Lawrence Berkeley National Laboratory in California, told Live Science. "But we can't ignore other data that extend to both the earlier and later universe. Combining [DESI's results] with those other data is when it gets truly weird, and it appears that this dark energy must be 'dynamic,' meaning that it changes with time."
Dark energy and dark matter are two of the universe's most puzzling components. Together they make up roughly 95% of the cosmos, but because they do not interact with light, they can't be detected directly.
Yet these components are key ingredients in the reigning Lambda cold dark matter (Lambda-CDM) model of cosmology, which maps the growth of the cosmos and predicts its end. In this model, dark matter is responsible for holding galaxies together and accounts for their otherwise inexplicably powerful gravitational pulls, while dark energy explains why the universe's expansion is accelerating.
Related: Could the universe ever stop expanding? New theory proposes a cosmic 'off switch'
But despite countless observations of these hypothetical dark entities shaping our universe, scientists are still unsure where they came from, or what they even are. Currently, the best theoretical explanation for dark energy is made by quantum field theory, which describes the vacuum of space as filled with a sea of quantum fields that fluctuate, creating an intrinsic energy density in empty space.
In the aftermath of the Big Bang, this energy increases as space expands, creating more vacuum and more energy to push the universe apart faster. This suggestion helped scientists to tie dark energy to the cosmological constant — a hypothetical inflationary energy, growing with the fabric of space-time throughout the universe's life. Einstein named it Lambda in his theory of general relativity.
"The problem with that theory is that the numbers don't add up," said Catherine Heymans, a professor of astrophysics at the University of Edinburgh and the Astronomer Royal for Scotland who was not involved in the study. "If you say: 'Well, what sort of energy would I expect from this sort of vacuum?' It's very, very, very, very different from what we measure," she told Live Science.
"It's kind of exciting that the universe has thrown us a curveball here," she added.
To figure out if dark energy is changing over time, the astronomers turned to three years' worth of data from DESI, which is mounted on the Nicholas U. Mayall 4-meter Telescope in Arizona. DESI pinpoints the monthly positions of millions of galaxies to study how the universe expanded up to the present day.
By compiling DESI's observations, which includes nearly 15 million of the best measured galaxies and quasars (ultra-bright objects powered by supermassive black holes), the researchers came up with a strange result.
Taken on their own, the telescope's observations are in "weak tension" with the Lambda-CDM model, suggesting dark energy may be losing strength as the universe ages, but without enough statistical significance to break with the model.
But when paired with other observations, such as the universe's leftover light from the cosmic microwave background, supernovas, and the gravitational warping of light from distant galaxies, the likelihood that dark energy is evolving grows.
In fact, it pushes the observations' disagreement with the standard model as far as 4.2 Sigma, a statistical measure on the cusp of the five-Sigma result physicists use as the "gold standard" for heralding a new discovery.
Related: After 2 years in space, the James Webb telescope has broken cosmology. Can it be fixed?
Whether this result will hold or fade over time with more data is unclear, but astrophysicists are growing confident that the discrepancy is less likely to disappear.
RELATED STORIES
—Cosmic voids may explain the universe's acceleration without dark energy
—'Heavy' dark matter would rip our understanding of the universe apart, new research suggests
—Something invisible and 'fuzzy' may lurk at the Milky Way's center, new research suggests
"These data seem to indicate that either dark energy is becoming less important today, or it was more important early in the universe," Schlegel said.
Astronomers say that further answers will come from a flotilla of new experiments investigating the nature of dark matter and dark energy in our universe. These include the Euclid space telescope, NASA's Nancy Grace Roman Space Telescope, and DESI itself, which is now in its fourth of five years scanning the sky and will measure 50 million galaxies and quasars by the time it's done.
"I think it's fair to say that this result, taken at face-value, appears to be the biggest hint we have about the nature of dark energy in the [rough] 25 years since we discovered it," Adam Riess, a professor of astronomy at Johns Hopkins University who won the 2011 Nobel Prize in physics for his team's 1998 discovery of dark energy, told Live Science. "If confirmed, it literally says dark energy is not what most everyone thought, a static source of energy, but perhaps something even more exotic."
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Yahoo
4 hours ago
- Yahoo
Giant 'X' appears over Chile as 2 celestial beams of light cross
When you buy through links on our articles, Future and its syndication partners may earn a commission. QUICK FACTS What it is: The luminous band of the Milky Way and the faint glow of zodiacal light Where it is: Cerro Tololo Inter-American Observatory, Chile When it was shared: Aug. 6, 2025 This stunning image from astrophotographer Petr Horálek captures two of the night sky's most glorious sights in one — the glowing heart of the Milky Way and the elusive "zodiacal light." Despite appearing alongside one another, these two streaks of light could not be more different in origin and composition. Astronomers have constructed some of humanity's best telescopes in the Southern Hemisphere to better see the bright core of the Milky Way — dense with stars and nebulae. That core passes through constellations including Scorpius, Sagittarius and Ophiuchus, which are higher in the sky the farther south they're viewed from. This image was taken at the Cerro Tololo Inter-American Observatory (CTIO), located at an altitude of 7,200 feet (2,200 meters) in the Chilean Andes within the southern Atacama Desert. At this height, above the densest and warmest part of Earth's atmosphere, incredibly clear and dark skies are the norm, enabling observers to see not only the bright band of the Milky Way but something less obvious that resides in the solar system — zodiacal light. The biggest visible solar system phenomenon in the night sky, zodiacal light is a faint, diffuse glow in the night sky that casual observers often miss. It consists of sunlight reflecting off dust in our cosmic neighborhood, possibly from passing asteroids and comets or from the leftovers of planet formation. In 2020, a paper also claimed that zodiacal light may be primarily made of dust blown off Mars. Either way, the glow of the solar system is an arresting sight, but hard to see. MORE SPACE PHOTOS —James Webb telescope captures one of the deepest-ever views of the universe —NASA unveils 9 stunning snapshots of the cosmos in X-ray vision —'Fighting dragons' light up little-known constellation in the Southern sky Zodiacal light is at its brightest around the equinoxes and is visible along the ecliptic — the apparent path the sun takes through the sky — as a triangular beam of light on the horizon a few hours before sunrise or after sunset. That timing has led to it being called either the "false dawn" or "false dusk," though its name comes from the fact that it's visible over the 13 constellations that make up the zodiac. Horálek's spectacular image was taken in 2022 when he was an audiovisual ambassador for NOIRLab, which operates CTIO. In the photo, from left to right, are the U.S. Naval Observatory Deep South Telescope, the DIMM1 Seeing Monitor, the Chilean Automatic Supernova Search dome, the UBC Southern Observatory and the Planetary Defense 1.0-meter Telescope. Solve the daily Crossword
Yahoo
4 hours ago
- Yahoo
'Sleeping giant' fault beneath Canada could unleash a major earthquake, research suggests
When you buy through links on our articles, Future and its syndication partners may earn a commission. A major fault in the Yukon, Canada, that has been quiet for at least 12,000 years may be capable of giving off earthquakes of at least magnitude 7.5, new research suggests. Based on the amount of strain the Tintina fault has accumulated over the past 2.6 million years, it is now under an amount of stress that could lead to a large quake within a human lifespan, researchers reported July 15 in the journal Geophysical Research Letters. The finding may require experts to rethink the earthquake danger in the region, the study authors said. An magnitude 7.5 earthquake would threaten a few small communities within the remote Yukon. But the finding that the Tintina fault may be capable of such a large quake is notable because the fault has been quiet since before the last ice age ended. "Major ancient faults like that can remain as weak zones in the Earth's crust and then focus ongoing tectonic strain," Theron Finley, a geoscientist who conducted the research while earning his doctorate at the University of Victoria in Canada, told Live Science. The Tintina fault is over 620 miles (1,000 kilometers) long and stretches from northeast British Columbia through the Yukon and into Alaska. On its southern end, it connects to the Rocky Mountain Trench fault, which creates a huge valley through southern Canada and northern Montana. Forty million years ago, during the Eocene epoch, one side of the Tintina fault slid 267 miles (430 km) against the other at a rate of about half an inch (13 millimeters) each year. Today, the fault seems quiet, with only occasional small earthquakes of magnitude 3 to 4 in some sections. However, "there has always been a question of whether it's still a little bit active or still accumulating strain at a slower rate," Finley said. To find out, Finley and his colleagues used high-resolution satellite data and lidar imagery of the Yukon. Lidar is a type of laser measurement that allows for precise imaging of topography while ignoring vegetation — an important tool for an area blanketed with forest. With this imagery, the researchers looked for signs on the surface of ancient earthquakes, such as fault "scarps," where the ground moved sharply upward on one side of the fault. "Those features can be hundreds of kilometers long in some cases, but they're only on the order of a couple meters high or wide, so we need the really high-resolution topographic data," Finley said. The researchers determined the dates of each rumple of the landscape by using traces left by incursions of glaciers, which occurred at known intervals 12,000 years ago, 132,000 years ago, and 2.6 million years ago. They found that over 2.6 million years, the fault's sides moved relative to each other by about 3,300 feet (1,000 m). Over the past 136,000 years, the opposing sides of the fault moved about 250 feet (75 m). It probably took hundreds of earthquakes to accumulate all that movement, Finley said, which translates to between 0.008 and 0.03 inches (0.2 to 0.8 mm) per year. The fault has not had a large earthquake that ruptured the ground surface for at least 12,000 years, according to the study. The researchers estimate that in that period, the fault has accumulated about 20 feet (6 m) of built-up strain — movement that hasn't yet been released in an earthquake. The fault probably breaks at between 3 and 33 feet (1 to 10 m) of strain, Finley said, so it's in the range where it might normally fracture. "It could still be many thousands of years before it reaches the threshold where it ruptures, but we don't know that and it's very hard to predict that," Finley said. Because the fault is active in its Alaska portion, it's not surprising to learn that the Tintina fault could be a sleeping giant, said Peter Haeussler, a geologist emeritus at the U.S. Geological Survey in Alaska. He said he was glad to see the evidence emerge."Somebody's finally found evidence for activity on the Tintina fault in the Yukon," Haeussler told Live Science. RELATED STORIES —There's a massive fault hiding under America's tallest mountain —Mystery magma reservoir found in volcanoless region of Alaska —Seattle's massive fault may result from oceanic crust 'unzipping itself' 55 million years ago "It ups the seismic hazard for this neck of the woods a little bit," he added, but not enormously, as the region was already known to be seismically active. The fault runs near Dawson City, Canada, Finley said, which has a population of about 1,600 and would be most threatened by a large quake. There are also mining facilities in the area, as well as a risk of quake-triggered landslides. To better understand the risk, geoscientists will need to excavate trenches in the fault to look for rock layers that show past earthquakes and how often they occurred. "Right now, we just know that many have occurred, but we don't have a sense of how frequently," Finley said. "Is 6 meters a lot of strain, or is it more likely there's a long way to go before another rupture?"
Yahoo
4 hours ago
- Yahoo
San Andreas fault could unleash an earthquake unlike any seen before, study of deadly Myanmar quake suggests
When you buy through links on our articles, Future and its syndication partners may earn a commission. Faults like San Andreas don't necessarily repeat past behavior, which means the next big earthquake in California has the potential to be larger than any seen before, a new study suggests. The fresh insights into fault behavior came from studying Myanmar's devastating March earthquake, which killed more than 5,000 people and caused widespread destruction. Scientists found that the fault responsible, an "earthquake superhighway" known as the Sagaing Fault, ruptured across a larger area, and in places that they wouldn't have expected based on previous events. Faults are fractures in Earth's crust. Stress can build up along the faults until eventually the fault suddenly ruptures, causing an earthquake. As the Sagaing and San Andreas faults are similar, what happened in Myanmar could help researchers better understand what might happen in California. "The study shows that future earthquakes might not simply repeat past known earthquakes," study co-author Jean-Philippe Avouac, a professor of geology and mechanical and civil engineering at Caltech, said in a statement. "Successive ruptures of a given fault, even as simple as the Sagaing or the San Andreas faults, can be very different and can release even more than the deficit of slip since the last event." Related: Almost half of California's faults — including San Andreas — are overdue for earthquakes The San Andreas Fault is the longest fault in California, stretching about 746 miles (1,200 kilometers) from the state's south at the Salton Sea to its north off the coast of Mendocino. In 1906, a rupture in the northern section of the fault caused a devastating magnitude 7.9 earthquake that killed more than 3,000 people, according to the U.S. Geological Survey. Earthquakes are notoriously unpredictable, but geologists have long warned that the San Andreas Fault will produce another massive earthquake at some point. For instance, the area nearest to Los Angeles has a 60% chance of experiencing a magnitude 6.7 or greater in the next 30 years, according to the USGS. The 870-mile-long (1,400 km) Sagaing Fault is similar to the San Andreas Fault in that they are both long, straight, strike-slip faults, which means the rocks slide horizontally with little or no vertical movement. Geologists were expecting the Sagaing Fault to slip somewhere along its extent. Specifically, they thought that the rupture would take place across a 190-mile-long (300 km) section of the fault where no large earthquakes had occurred since 1839. This expectation was based on the seismic gap hypothesis, which anticipates that a stuck section of a fault — where there hasn't been movement for a long time — will slip to catch up to where it was, according to the statement. RELATED STORIES —First-of-its-kind video captures the terrifying moment the ground tore apart during major Myanmar earthquake —Russia earthquake: Magnitude 8.8 megaquake hits Kamchatka, generating tsunamis across the Pacific —'Sleeping giant' fault beneath Canada could unleash a major earthquake, research suggests However, in the case of Sagaing, the slip occurred along more than 310 miles (500 km) of the fault, meaning that it caught up and then some. The researchers used a special technique to correlate satellite imagery before and after the event. Those images revealed that after the earthquake, the eastern side of the fault moved south by about 10 feet (3 m) relative to the western side. The scientists say that the imaging technique they used could help improve future earthquake models. "This earthquake turned out to be an ideal case to apply image correlation methods [techniques to compare images before and after a geological event] that were developed by our research group," study first author Solène Antoine, a geology postdoctoral scholar at Caltech, said in the statement. "They allow us to measure ground displacements at the fault, where the alternative method, radar interferometry, is blind due to phenomenon like decorrelation [a process to decouple signals] and limited sensitivity to north–south displacements."
