All articles tagged with #dark matter
Physicists modeling ultralight dark matter around merging black holes suggest the July 2019 LVK event GW190728 could reflect a dense dark matter cloud, imprinting signatures on the gravitational waves. While intriguing, the statistical significance is not yet strong enough to claim a detection, and independent checks are needed; if confirmed, it would open a new way to study dark matter and its interaction with spacetime.
Astronomers using the VLT's MUSE instrument captured the clearest image yet of a cosmic filament—about 3 million light-years long—connecting two actively forming galaxies when the universe was ~2 billion years old. The direct detection of faint intergalactic gas, traveling roughly 12 billion years to Earth, aligns with simulations and offers new insight into how gas flows through the cosmic web to fuel galaxy growth and star formation.
Using the James Webb Space Telescope, astronomers captured LAP1-B, one of the universe’s earliest and faint galaxies, dating to about 13 billion years ago (roughly 800 million years after the Big Bang). Gravitational lensing by a foreground cluster amplified its light ~100x, enabling spectroscopy that reveals extremely low metal content and signatures of Population III stars, including a high carbon-to-oxygen ratio. The data also suggest the galaxy sits in a massive dark matter halo, offering critical clues about how the first galaxies formed and evolved in the early cosmos (Nature).
A new study proposes that dense dark-matter clouds around spinning black holes could imprint a detectable signal on gravitational waves produced by merging black holes. Researchers analyzed 28 LIGO/Virgo/KAGRA events and found one—GW190728—whose waveform may carry such an imprint, though not a definitive detection. If true, this could provide a new way to probe dark matter using upcoming gravitational-wave observations and detector improvements, with the results published in Physical Review Letters.
A large American Physical Society survey of 1,600+ physicists and science enthusiasts reveals broad disagreement on core cosmology topics. While 68% view the Big Bang as a hot, dense state (not necessarily a definite beginning), 20% see it as the absolute beginning with a singularity. On dark matter, only 10% endorse the traditional WIMP view, with about 21% proposing a hybrid of ideas, and on dark energy, 24% see it as a constant while 26% think it evolves over time, per DESI. The results highlight that scientific consensus is tenuous and progress comes from continued testing and debate.
MIT and European researchers developed a numerical model predicting how black-hole mergers would imprint dark matter on gravitational waves. When applied to LVK data, 27 of 28 clearest events matched vacuum expectations, while GW190728 showed a possible dark-matter imprint—though not a confirmed detection. The method provides a new way to screen for dark-matter signatures in gravitational waves for follow-up studies.
New simulations indicate the Milky Way sits inside a vast, flattened sheet of matter dominated by dark matter, extending tens of millions of light-years. This planar mass distribution helps explain why nearby galaxies mostly drift away rather than be drawn toward the Milky Way, matching the observed motions of over 30 neighboring galaxies. Further observations will show whether such cosmic sheets are common elsewhere and how they shape galaxy formation.
Using the kinematic Sunyaev-Zeldovich effect on about 686,000 galaxies in clusters 5–7 billion light-years away, researchers measured cluster speeds and found gravity weakens with distance consistent with Newtonian/Einsteinian gravity, strengthening the case for dark matter as the source of anomalous gravitational effects, though many questions remain. The study was published in Physical Review Letters.
On Pop Mech's episode, physicists speculate a curled or warped fifth dimension could coexist with our universe, with some particles slipping into it and effectively disappearing from our reality—a theory that could help explain dark matter and prompts discussion of warped spacetime and gravitational waves.
A new self-interacting dark matter theory proposes that dark matter particles collide with one another to form dense cores, potentially explaining three puzzling observations: an ultradense dark matter clump in the gravitationally lensed system JVAS B1938+666, a visible “scar” in the GD-1 stellar stream, and the unusual formation of the Fornax 6 star cluster in the Milky Way’s Fornax dwarf galaxy. The mechanism, related to gravothermal collapse, could unify these disparate clues across cosmic scales in a way standard collisionless dark matter cannot.
The FLAMINGO project released a self‑consistent, hydrodynamical cosmological dataset (over 2.5 PB) that simulates dark matter, ordinary matter, and dark energy across vast scales, enabling study of galaxy formation and rare cosmic events while providing open access for researchers to compare models with upcoming observations.
A theoretical team proposes a previously unknown heavy particle that mixes with the Higgs boson to act as a conduit between visible matter and dark matter residing in a warped fifth dimension. This could help explain fermion masses and the dark-to-visible matter ratio, but the particle would be too heavy for current colliders; future machines or gravitational-wave observations might provide indirect evidence.
Researchers propose that energy from decaying dark matter could heat primordial gas enough to trigger direct-collapse black holes, potentially seeding the universe's first SMBHs earlier than standard growth models. The idea, spurred by JWST observations of massive black holes within the first billion years, pinpoints a 24–27 eV dark-matter particle as a possible energy source and was published in JCAP on April 14.
The European Space Agency’s Euclid survey has released a massive data set (about 72 million galaxies, roughly 30 times larger than earlier) and invites the public to help identify gravitational lenses via the Space Warps citizen-science project. AI has pre-selected around 300,000 candidate images, but human inspection remains key to spotting the subtle arcs and rings. The goal is to discover more than 10,000 new lenses, with early results from just 0.04% of the data yielding 500 lenses, enabling scientists to measure total mass (including dark matter) and study cosmic expansion. No physics degree is required—just curiosity.
A new study proposes that dark matter could be relic primordial black holes surviving a prior cosmic collapse in a Big Bounce, meaning dark structures in galaxies might be remnants from a previous universe. These relic black holes (and associated gravitational waves and density fluctuations) could constitute a significant fraction of dark matter, though the idea must be tested against data from gravitational waves, galaxy surveys, and the cosmic microwave background.