Physicists have put a decades-old idea about why the strange rules of quantum mechanics disappear in our everyday world to one of its toughest experimental tests yet. Deep beneath Italy’s Gran Sasso mountain, researchers searched for an extremely faint radiation signal predicted by a theory suggesting that tiny fluctuations in spacetime, caused by gravity, gradually destroy quantum superpositions. After 62 days of measurements with a highly shielded germanium detector, they found no such signal.

A decade-long NIST experiment has produced a new measurement of the universal gravitational constant that differs unexpectedly from another leading result, deepening a 225-year-old physics puzzle. The discrepancy is tiny, but for one of nature’s most fundamental constants, it is large enough to keep scientists wondering whether hidden experimental errors or something more surprising is involved.

Common preservatives hiding in processed foods may carry unexpected heart risks, with heavy consumption linked to substantially higher rates of high blood pressure and cardiovascular disease. Researchers identified eight widely used preservatives associated with hypertension, although the observational study cannot prove they were directly responsible.

A sweeping review of more than 153,000 adults found that calcium and vitamin D supplements, alone or together, do little to prevent fractures or falls in most older people. Researchers say the findings challenge routine supplementation for prevention and point instead toward strategies such as balance and resistance exercise.

Researchers may have solved a long-running mystery surrounding the Dead Sea Scrolls by proposing that the Qumran sect really did use its distinctive 364-day calendar. Its perfectly ordered 52-week system kept holidays on the same weekdays, but it slowly drifted out of sync with the seasons because it was shorter than the true solar year.

Cats may identify one another through a surprisingly durable chemical “calling card” made from 13 unusual fatty acids in their urine. The compounds appear linked to mysterious fat droplets in the kidneys and may represent a scent-recognition system shared across the cat family.

Scientists have developed ultra-bright nanoparticles that can detect tiny amounts of chemicals and distinguish between molecules that look almost identical. The technology could one day provide a cheaper way to catch dangerous drug impurities or trace pollutants using simple low-cost lasers.

Ancient DNA reveals that plague repeatedly returned to Europe for more than 400 years after the Black Death, evolving into new lineages and spreading through trade, migration, and war. Researchers also developed a method to date ancient plague genomes more precisely, linking many of them to specific outbreaks recorded in historical sources.

Physicists have detected strong evidence that heavy, fleeting Z bosons can become quantum entangled during Higgs boson decays at CERN’s Large Hadron Collider. The result shows that Einstein’s “spooky action at a distance” survives even under some of the most extreme conditions ever created in a laboratory.

Chemical clues preserved inside fossilized T. rex teeth reveal that the dinosaur maintained a body temperature of about 97 degrees Fahrenheit, almost identical to humans. The finding provides direct evidence that the giant predator was warm-blooded, helping explain how it stayed active and survived in chilly environments as far north as Alaska.

A growing Bundibugyo virus outbreak is showing how a little-known relative of Ebola can become a major threat when diagnosis and treatment options are limited. Experts warn that preparing only for familiar pathogens could leave the world vulnerable when rare but deadly viruses suddenly reemerge.

A massive crater on Mars’ moon Phobos may hide a dense region of compressed material that could reveal whether the moon is a captured asteroid or debris from an ancient impact on Mars. Japan’s upcoming MMX sample return mission could provide the measurements and physical evidence needed to solve the mystery.

Nearly three decades of Hurricane Hunter data reveal four features that can help a tilted tropical cyclone straighten its circulation and become capable of intensifying. The findings could give forecasters an earlier warning that a seemingly disorganized storm is becoming primed to strengthen.

Complex systems may work better when their parts are not perfectly alike. Northwestern physicists found that carefully balanced variation, or “disorder,” can make networks such as power grids, ecosystems, neurons, and materials more stable. Even random differences sometimes improved stability compared with completely uniform systems. The discovery could help researchers design more resilient technologies and explain why natural systems are so rarely perfectly uniform.

A chemical that stops drywood termites from building new exoskeletons killed about 95% of colonies in testing, offering a potentially safer alternative to traditional fumigation. Because termites eventually have no choice but to molt, the treatment turns a normal stage of their life cycle into a fatal weakness.

Scientists have identified the genetic cause behind the mysterious AnWj blood group antigen, solving a puzzle that began in 1972 and establishing a new blood group system called MAL. The discovery could make it much easier to find extremely rare AnWj-negative patients and donors and protect them from potentially dangerous transfusion reactions.

Researchers have uncovered a hidden molecular warning sign of inflammatory bowel disease (IBD) that can linger even when patients feel well and appear to be in remission. By studying around 900 human gut biopsies and patient-derived mini-intestines, the team found that intestinal cells can remain unusually primed to die, creating a “smoldering” defect that may help drive future flare-ups.

A single-celled organism can shrink to one-quarter of its length in milliseconds using a remarkable calcium-powered protein “fishnet.” Scientists hope its unusual machinery could inspire artificial muscles capable of moving far faster than today’s designs.

A deep-sea microbe uses an exceptionally heat-resistant enzyme to turn atmospheric nitrogen into ammonia at temperatures that would destroy most proteins. Its unusual structure and a newly observed reaction state may reveal an ancient, shared mechanism behind nitrogen fixation and could eventually inspire cleaner biotechnology and fertilizer production.

A 150-million-year-old dinosaur fossil from Spain has been identified as the first confirmed Diplodocus ever found outside North America. The giant sauropod measured about 25 meters long and was preserved well enough for researchers to match distinctive features in its tail bones to the famous genus. Its unexpected appearance in Europe suggests dinosaurs were moving between the continents during the Late Jurassic, possibly across temporary land connections.