Gravitational waves

This week, among a lot of other important findings, we learned that emperor cichlid fish have gaze sensitivity and dislike it if you look at them—or especially their children. England is looking for a solution to its 5-billion-liter water deficit. And a high-fiber diet isn't only healthy for you—it also benefits your parasitic tapeworms!

Gravitational waves are ripples in spacetime produced by violent cosmic events, such as the merging of black holes. So far, direct detections have relied on measuring tiny distance changes over kilometer-scale instruments. In a new theoretical study published in Physical Review Letters, researchers at Stockholm University, Nordita, and the University of Tübingen propose an unconventional approach: tracking how gravitational waves reshape the light emitted by atoms. The work describes a possible detection route, but an experimental demonstration remains for the future.

A new data release more than doubles the number of gravitational-wave candidate events—and reveals unexpected complexities of merging black holes

When the densest objects in the universe collide and merge, the violence sets off gravitational waves that reverberate

Neutron stars harbor some of the most extreme environments in the universe: their densities soar to several times those of atomic nuclei, and they possess some of the strongest gravitational fields of any known objects, surpassed only by black holes. First observed in the 1960s, much of the internal composition of neutron stars is still unknown. Scientists are beginning to look to gravitational waves emitted by binary neutron‐star inspirals—pairs of mutually orbiting neutron stars—as possible sources of information about their interiors.

A new study published in Nature Astronomy indicates that the dense, star- and dark-matter–rich environments around supermassive black hole binaries pack on the order of a million solar masses into each cubic parsec. The team used gravitational-wave data from pulsar timing arrays to probe galactic centers that are otherwise impossible to observe directly.

When the densest objects in the universe collide and merge, the violence sets off ripples, in the form of gravitational waves, that reverberate across space and time, over hundreds of millions and even billions of years. By the time they pass through Earth, such cosmic ripples are barely discernible.

Neutron stars are ultra-dense remnants of massive stars that collapsed after supernova explosions and are made up mostly of subatomic particles with no electric charge (i.e., neutrons). When two neutron stars collide, they are predicted to produce gravitational waves, ripples in the fabric of spacetime that travel at the speed of light.

On 14 January, 2025, two colliding black holes sent the clearest gravitational wave signal ever recorded rippling across the universe to Earth’s detectors. This remarkably crisp signal, designated GW250114, has allowed physicists to conduct the most stringent test yet of Einstein’s general relativity by measuring multiple “tones” from the collision. The wave passed the test with flying colours, but researchers remain optimistic that future detections might finally reveal where Einstein’s century old theory breaks down, potentially offering the first glimpses of quantum gravity.

The universe is a big place, and tracking down some of the more interesting parts of it is tricky. Some of the most interesting parts of it, at least from a physics perspective, are merging black holes, so scientists spend a lot of time trying to track those down. One of the most recent attempts to do so was published in The Astrophysical Journal Letters by the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) collaboration. While they didn’t find any clear-cut evidence of continuous gravitational waves from merging black hole systems, they did manage to point out plenty of false alarms, and even disprove some myths about ones we thought actually existed.

A record-breaking gravitational wave signal let scientists "listen" to a distant black hole merger and put Einstein's gravity to its toughest test yet.

Ripples in space-time from a pair of merging black holes have been recorded in unprecedented detail, enabling physicists to test predictions of general relativity

An international collaboration of astrophysicists that includes researchers from Yale has created and tested a detection system that uses gravitational waves to map out the locations of merging black holes—known as supermassive black hole binaries—around the universe. Such a map would provide a vital new way to explore and understand astronomy and physics, just as X-rays and radio waves did in earlier eras, the researchers say. The new protocol demonstrated by the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) offers a detection protocol to populate the map.

A newly detected gravitational wave, GW250114, is giving scientists their clearest look yet at a black hole collision—and a powerful way to test Einstein’s theory of gravity. Its clarity allowed scientists to measure multiple “tones” from the collision, all matching Einstein’s predictions. That confirmation is exciting—but so is the possibility that future signals won’t behave so neatly. Any deviation could point to new physics beyond our current understanding of gravity.

For those who watch gravitational waves roll in from the universe, GW250114 is a big one. It's the clearest gravitational wave signal from a binary black hole merger to date, and it gives researchers an opportunity to test Albert Einstein's theory of gravity, known as general relativity.

Author(s): Jamie Bamber, Antonios Tsokaros, Milton Ruiz, Stuart L. Shapiro, Marc Favata, Matthew Karlson, and Fabrizio Venturi PiñasThe full displacement memory signal from binary neutron star mergers, including both the contribution from the gravitational waves themselves and from the electromagnetic, neutrino and baryonic ejecta is quantified using general relativistic magnetohydrodynamic simulations. [Phys. Rev. Lett. 136, 041401] Published Mon Jan 26, 2026

Scientists at the University of Colorado Boulder may have solved a pressing mystery about the universe's gravitational wave background.

A new study by researchers at the University of Amsterdam shows how gravitational waves from black holes can be used to reveal the presence of dark matter and help determine its properties. The key is a new model, based on Einstein’s theory of general relativity, that tracks in detail how a black hole interacts with the surrounding matter.

Gravitational waves from black holes may soon reveal where dark matter is hiding. A new model shows how dark matter surrounding massive black holes leaves detectable fingerprints in the waves recorded by future space observatories.

A new study by researchers at the University of Amsterdam shows how gravitational waves from black holes can be used to reveal the presence of dark matter and help determine its properties. The key is a new model, based on Einstein's theory of general relativity, that tracks in detail how a black hole interacts with the surrounding matter.

Author(s): Laura Bernard, Suvendu Giri, Luis Lehner, and Riccardo SturaniTreating deviations from general relativity (GR) in the framework of effective field theories (EFT), the authors develop a formalism for computing gravitational waveforms in the inspiral phase of binary black hole coalescence. The authors work within the post-Newtonian expansion to characterize the deviations. These results can be used in ongoing experimental tests of GR in the inspiral phase. [Phys. Rev. D 112, 124013] Published Wed Dec 03, 2025

Scientists may have "heard" the first tantalizing evidence of primordial black holes formed directly from overly dense pockets of matter just after the Big Bang.

Forty years after their invention, laser systems based on non-planar ring oscillators (NPROs) are among the most important

Astronomers approach unusual observation with caution and excitement

Black holes, regions of spacetime in which gravity is so strong that nothing can escape, are intriguing and extensively studied cosmological phenomena. Einstein's general theory of relativity predicts that when two black holes merge, they emit ripples in spacetime known as gravitational waves.

Learn about two black hole mergers in 2024 that experts revisited with new information from gravitational waves, confirming theories made by Albert Einstein.

Current gravitational wave observatories can't see a range of frequencies known as mid-band. That could change with a new detector that uses a trick from atomic clocks.

In a paper published in The Astrophysical Journal Letters, the international LIGO-Virgo-KAGRA Collaboration reports on the detection of two gravitational wave events in October and November of 2024 with unusual black hole spins. This observation adds an important new piece to our understanding of the most elusive phenomena in the universe.

FROnt Surface Type Irradiator, or FROSTI, will allow future detectors to run at higher laser powers, reducing noise and expanding capabilities The post New adaptive optics technology boosts the power of gravitational wave detectors appeared first on Physics World.

Astronomers are listening for cosmic gravitational waves in the rhythm of pulsars. But even after finding them, they will need to distinguish between cosmic waves and the more local waves of black holes.

Author(s): Keisuke Inomata, Marc Kamionkowski, Kentaro Kasai, and Bibhushan ShakyaIn this paper, the authors discuss a new source of gravitational waves from first order phase transitions. The collision of bubbles in the new phase can efficiently produce particles that couple to the background field undergoing the transition, transferring a significant amount of the released vacuum energy into particle populations that long outlive the bubbles and provide a novel source of gravitational waves. [Phys. Rev. D 112, 083523] Published Tue Oct 14, 2025

A new paper outlines a method to distinguish between sources of nanohertz gravitational waves.

Pulsars suggest that ultra–low-frequency gravitational waves are rippling through the cosmos. The signal seen by international pulsar timing array collaborations in 2023 could come from a stochastic gravitational-wave background—the sum of many distant sources—or from a single nearby binary of supermassive black holes.

Global network could pinpoint astronomical sources The post Phase shift in optical cavities could detect low-frequency gravitational waves appeared first on Physics World.

The world's most sensitive table-top interferometric system—a miniature version of miles-long gravitational-wave detectors like LIGO—has completed its first science run.

Author(s): Valentin Boyanov, Vitor Cardoso, Kostas D. Kokkotas, and Jaime Redondo-YusteA neutron star’s viscosity determines how the star interacts with gravitational waves, a behavior that could be useful to the study of neutron-star interiors. [Phys. Rev. Lett. 135, 151402] Published Wed Oct 08, 2025

Author(s): Sumanta ChakrabortyA neutron star’s viscosity determines how the star interacts with gravitational waves, a behavior that could be useful to the study of neutron-star interiors. [Physics 18, 169] Published Wed Oct 08, 2025

Author(s): Tomasz Baka, Harsh Narola, Justin Janquart, Anuradha Samajdar, Tim Dietrich, and Chris Van Den BroeckThe problem of overlapping signals in gravitational wave astronomy refers to situations where signals from distinct events overlap in time. They pose a challenge for distinguishing the sources of the signals and accurately performing parameter estimation. This paper proposes an approach to addressing this issue for next-generation gravitational wave detectors. [Phys. Rev. D 112, 082001] Published Fri Oct 03, 2025

Researchers have designed a new type of gravitational wave detector that operates in the milli-Hertz range, a region untouched by current observatories. Built with optical resonators and atomic clocks, the compact detectors can fit on a lab table yet probe signals from exotic binaries and ancient cosmic events. Unlike LIGO, they’re relatively immune to seismic noise and could start working long before space missions like LISA launch.

Physicists have proposed a new way to detect elusive gravitational waves in the ‘midband’. These waves are generated by binary systems of white dwarfs and neutron stars in the Milky Way and black hole mergers but are not detectable with current instruments. The approach uses ‘optical resonator’ technology originally developed for optical atomic clocks, which […]

Scientists have unveiled a new approach to detecting gravitational waves in the milli-Hertz frequency range, providing access to astrophysical and cosmological phenomena that are not detectable with current instruments.

In this podcast we also make predictions for this year’s physics award The post The curious history of Nobel prizes: from lighthouses to gravitational waves appeared first on Physics World.

Gravitational-wave detection technology is poised to make a big leap forward thanks to an instrumentation advance led by physicist Jonathan Richardson of the University of California, Riverside. A paper detailing the invention, published in the journal Optica, reports the successful development and testing of FROSTI, a full-scale prototype for controlling laser wavefronts at extreme power levels inside the Laser Interferometer Gravitational-Wave Observatory, or LIGO.

Interference from human activity has always been a sticking point in astronomical observations. Radio astronomy is notoriously sensitive to unintentional interference—hence why there are "radio silent" zones near telescopes where cell phones are banned. But gravitational wave astronomy is affected to an even worse degree than radio astronomy, according to a new paper published on the arXiv preprint server by Reed Essick of the University of Toronto, and it's not clear there's much we can do about it.

On Sept. 14, 2015, a signal arrived on Earth, carrying information about a pair of remote black holes

Ten Years Later, LIGO is a Black-Hole Hunting Machine lexigault60428 Fri, 09/12/2025 - 10:00 Ten Years Later, LIGO is a Black-Hole Hunting Machine https://www.caltech.edu/about/news/ten-years-later-ligo-is-a-black-hole-hunting-machine

The Einstein Telescope could usher in a new age of gravitational-wave astronomy The post Celebrating 10 years of gravitational waves appeared first on Physics World.

On September 14, 2015, a signal arrived on Earth, carrying information about a pair of remote black holes that had spiraled together and merged. The signal had traveled about 1.3 billion years to reach us at the speed of light—but it was not made of light. It was a different kind of signal: a quivering of space-time called gravitational waves first predicted by Albert Einstein 100 years prior.

The first-ever detection of gravitational waves was made 10 years ago today (Sept. 14). In celebration, Space.com takes you through the most significant gravitational wave discoveries to date.

When LIGO detected gravitational waves unleashed from two colliding black holes for the first time in science history, it set off a whole new era in astronomy.

Ten years after scientists first detected gravitational waves emerging from two colliding black holes, the LIGO-Virgo-KAGRA collaboration, a research team that includes Columbia astronomy professor Maximiliano Isi, has recorded a signal from a nearly identical black hole collision.

This week, researchers reported on a new biopsy tool that can detect HPV-associated head and neck cancer up to 10 years before symptoms appear. Researchers developed a process to transform two-dimensional paintings into full-color, three-dimensional holograms, providing a new way to experience art in a gallery setting. And Chinese scientists designed a physical cassette capable of storing massive amounts of data encoded as DNA on a polyester-nylon tape substrate.

Nature is the foremost international weekly scientific journal in the world and is the flagship journal for Nature Portfolio. It publishes the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature publishes landmark papers, award winning news, leading comment and expert opinion on important, topical scientific news and events that enable readers to share the latest discoveries in science and evolve the discussion amongst the global scientific community.

Nature is the foremost international weekly scientific journal in the world and is the flagship journal for Nature Portfolio. It publishes the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature publishes landmark papers, award winning news, leading comment and expert opinion on important, topical scientific news and events that enable readers to share the latest discoveries in science and evolve the discussion amongst the global scientific community.

Ten years ago, scientists heard the universe rumble for the first time. That first discovery of gravitational waves proved a key prediction from Albert Einstein's theory of general relativity and began a new era of astronomy.

Author(s): Chiara M. F. MingarelliThe clearest black hole merger signal ever measured has allowed researchers to test the Kerr nature of black holes and validate Stephen Hawking’s black hole area theorem. [Physics 18, 160] Published Wed Sep 10, 2025

Machine learning system reduces noise in interferometer mirrors The post LIGO could observe intermediate-mass black holes using artificial intelligence appeared first on Physics World.

Ten years ago, astronomers made an epic discovery with the Laser Interferometer Gravitational-Wave Observatory. Cosmology hasn’t been the same since, and it might not stay that way much longer.

An exceptionally loud collision between two black holes has been detected by the LIGO gravitational wave observatory, enabling physicists to test a theorem postulated by Stephen Hawking in 1971

Observations of gravitational waves produced by 2 black holes colliding and merging have allowed scientists to confirm fundamental predictions made by Albert Einstein and Stephen Hawking about the nature of the universe. “This is the clearest view yet of the nature of black holes,” says astrophysicist Maximiliano Isi, who co-led the analysis published in the […]

Celebrating 10 years since the first detection of gravitational waves coming from colliding black holes, LIGO has confirmed the predictions of the greatest minds in physics.

Ten years after LIGO’s historical detection of gravitational waves, the project is cracking black hole mysteries at an astounding pace.

Scientists have confirmed two long-standing theories relating to black holes—thanks to the detection of the most clearly recorded gravitational wave signal to date.

Ten years ago, astronomers made an epic discovery with the Laser Interferometer Gravitational-Wave Observatory. Cosmology hasn’t been the same since, and it might not stay that way much longer.

Ten years after the first gravitational waves were detected, the location and design for a third-generation gravitational-wave detector are being decided The post Physicists set to decide location for next-generation Einstein Telescope appeared first on Physics World.

A team of researchers led by the Instituto Galego de Física de Altas Enerxías (IGFAE) from the University of Santiago de Compostela (Spain) has measured for the first time the speed and direction of the recoil of a newborn black hole formed through the merger of two others. The result, published today in the journal Nature Astronomy, offers new insights into some of the most extreme events in the universe.

Nature is the foremost international weekly scientific journal in the world and is the flagship journal for Nature Portfolio. It publishes the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature publishes landmark papers, award winning news, leading comment and expert opinion on important, topical scientific news and events that enable readers to share the latest discoveries in science and evolve the discussion amongst the global scientific community.

Nature is the foremost international weekly scientific journal in the world and is the flagship journal for Nature Portfolio. It publishes the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature publishes landmark papers, award winning news, leading comment and expert opinion on important, topical scientific news and events that enable readers to share the latest discoveries in science and evolve the discussion amongst the global scientific community.

Experts at the Laser Interferometer Gravitational-Wave Observatory (LIGO) and Google DeepMind have trained an artificial intelligence program to dampen pesky background vibrations which drown out signals from the mergers of binary neutron stars and potential intermediate-mass black holes. “We were already at the forefront of innovation, making the most precise measurements in the world, but […]

The US National Science Foundation LIGO (Laser Interferometer Gravitational-wave Observatory) has been called the most precise ruler in

LIGO, the Laser Interferometer Gravitational-wave Observatory, has been called the most precise ruler in the world for its ability to measure motions more than 10,000 times smaller than the width of a proton. By making these extremely precise measurements, LIGO, which consists of two facilities—one in Washington and one in Louisiana—can detect undulations in space-time called gravitational waves that roll outward from colliding cosmic bodies such as black holes.

Astronomers have doubled the number of black hole and neutron star mergers detected via gravitational waves in a "stellar graveyard," as well as "hearing" the heaviest black hole binary yet.

A new Big Bang model does away with speculative elements, putting gravitational waves at the forefront of the creation of galaxies, stars, and planets.

Beloved physicist sketched out the concept that would lead to one of the biggest discoveries in physics and astronomy

MIT professor, Nobel prize winner, and renowned astrophysicist Rainer Weiss has passed away at the age of 92.

Weiss was instrumental in the discovery of gravitational waves in 2015 The post Rainer Weiss: US gravitational-wave pioneer dies aged 92 appeared first on Physics World.

Author(s): Benjamin Leather, Alessandra Buonanno, and Maarten van de MeentSelf-force theory, while initially adapted for the extreme mass-ratio case of the gravitational two-body problem, has in fact applications in wider contexts. Here, the approach is incorporated into effective one-body theory to develop a waveform model for the entire non-spinning binary coalescence process: inspiral, plunge, merger, and ringdown. Where the approaches can be compared, the model is found to be highly competitive in relation to existing waveform models and numerical relativity. [Phys. Rev. D 112, 044012] Published Thu Aug 07, 2025

A team of scientists has proposed a groundbreaking new theory on the Universe's origins, offering a fresh, radical take on the Big Bang's early moments. Unlike the widely accepted inflationary model, which involves speculative assumptions, the new model starts with the established concept of De Sitter space, aligning with dark energy observations. The scientists believe gravitational waves—ripples in space-time—were the key to seeding the formation of galaxies and cosmic structure, eliminating the need for unknown elements.

Less than a decade since the first detection of gravitational waves—ripples in spacetime itself—proposed budget cuts threaten to silence this groundbreaking science

After 10 years of gravitational-wave research, the LIGO Lab team at MIT is getting ready for the next generation of detectors.

Merger creates black holes weighing 240 times the mass of our Sun.

A new method to analyze gravitational-wave data could transform how we study some of the universe's most extreme events—black holes smashing into each other.

The largest black hole merger ever observed has resulted in a new black hole about 225 times the mass of our Sun. The collision was detected using the LIGO gravitational wave observatories. Gravitational waves were first detected at the US Laser Interferometer Gravitational-Wave Observatory (LIGO) in 2015. These waves, first postulated by Einstein in his […]

Gravitational-wave detectors have captured their biggest spectacle yet: two gargantuan, rapidly spinning black holes likely forged by earlier smash-ups fused into a 225-solar-mass titan, GW231123. The record-setting blast strains both the sensitivity of LIGO-Virgo-KAGRA and the boundaries of stellar-evolution theory, forcing scientists to rethink how such cosmic heavyweights arise.

Gravitational wave detectors have "heard" the ripples in space caused by the most massive black hole merger yet. One "forbidden" by current theoretical models.

A puzzling gravitational wave was detected, and astronomers have determined that it comes from a record-breaking black hole merger

The LIGO-Virgo-KAGRA (LVK) Collaboration has detected the merger of the most massive black holes ever observed with gravitational waves using the LIGO observatories. The powerful merger produced a final black hole approximately 225 times the mass of our sun. The signal, designated GW231123, was detected during the fourth observing run of the LVK network on November 23, 2023.

When Einstein's predicted ripples in spacetime pass through magnetic fields, they cause the current carrying wires to dance at the gravitational wave frequency, creating potentially detectable electrical signals. Researchers have discovered that the same powerful magnets used to hunt for dark matter could double as gravitational wave detectors. This means experiments already searching for the universe's most elusive particles could simultaneously capture collisions between black holes and neutron stars, getting two of physics' most ambitious experiments for the price of one, while potentially opening entirely new windows into the universe's most violent events.

Gravitational waves come in all shapes and sizes - and frequencies. But, so far, we haven’t been able to capture any of the higher frequency ones. That’s unfortunate, as they might hold the key to unlocking our understanding of some really interesting physical phenomena, such as Boson clouds and tiny block hole mergers. A new paper from researchers at Notre Dame and Caltech, led by PhD student Christopher Jungkind, explores how we might use one of the world’s most prolific gravitational wave observatories, GEO600, to capture signals from those phenomena for the first time.

When black holes need a place to crash, they prefer a nice, bright quasar.

New research published in Physical Review Letters suggests that superconducting magnets used in dark matter detection experiments could function as highly precise gravitational wave detectors, thereby establishing an entirely new frequency band for observing these cosmic ripples.

New mathematical technique is inspired by particle physics The post Black-hole scattering calculations could shed light on gravitational waves appeared first on Physics World.

In a new Physical Review Letters study, researchers have successfully followed a gravitational wave's complete journey from the infinite past to the infinite future as it encounters a black hole.