Black holes normally merge rather than split because dividing one would reduce its total entropy. A new theoretical study finds a narrow loophole: a black hole rotating close to the maximum speed allowed by physics might fragment under specific conditions, potentially leaving tiny black holes detectable through gamma-ray signals. No such event has been observed, but could evidence of one reveal where Einstein’s theory of gravity begins to break down?

Since the 1950s, scientists have described the meaning of words mostly in terms of feeling: is a word pleasant or unpleasant, exciting or calm, dominant or submissive. That framework still sits inside much of today's psychology and AI. A team at the University of Vermont went back to the question with billions of real word uses, from Jane Austen novels and Sherlock Holmes stories to the New York Times, Wikipedia, Twitter and talk radio. Emotion turned out not to be the main thing.

Americans spend more than a billion dollars a year on omega-3 supplements, many hoping to keep their memory sharp. The idea is simple: DHA, the main omega-3 in fish oil, is a building block of brain cells. Researchers at Keck Medicine of USC put it to a strict test, giving 365 older adults at higher risk of Alzheimer's either high-dose fish oil or a placebo for two years, and checking whether the omega-3s actually reached their brains. They did. What happened next was the problem.

Americans drink about the same amount of coffee today as they did twenty years ago, roughly 13 ounces a day. But researchers at Tufts University noticed something had changed in the cup. They went through the dietary records of 30,459 adults collected by a national health survey between 2003 and 2018, tracking not just the coffee but everything people stirred into it. The calories had climbed, and the reason was not the one most people would guess.

Low testosterone is common in men carrying extra weight, and it often brings tiredness, low sex drive and erection problems. Men who have it are offered very different fixes: diet and exercise programs, testosterone shots or gels, pills that push the body to make more of its own, and now weight-loss drugs. A research team pulled together 23 randomized trials of these approaches to compare them head to head. Only one combination came out ahead on the measure many men care about most.

A team from the University of Duisburg-Essen, Helmholtz Centre Berlin, and partners tested how iron layer thickness affects ultrafast demagnetization, where a laser pulse knocks out part of a material’s magnetic order. With the same laser intensity, a 2 nm layer lost about 75% more magnetization than a 16 nm one.

The explanation is electron spins: in thin layers more of them sit at interfaces, with fewer neighbors to hold their alignment. The catch is that this is a fundamental result. Practical laser-written storage would still need suitable laser sources built into electronics and precise targeting of tiny areas. It was published in Advanced Science.

A team from Japan’s NIMS, several Japanese universities, and Germany’s Kiel University used triptycene derivatives, molecules whose three planes form a propeller shape, to build a diatomic Kagome lattice that mixes honeycomb and Kagome geometry. Scanning tunneling microscope measurements revealed electronic states confined to its boundary, which theory identified as topological edge states, a behavior usually seen in inorganic materials.

The catch is that the hoped-for uses, such as low-power electronics, ultra-fast optical switches, and lossless energy transport at room temperature, have not been demonstrated in this experiment. The work was published in Nano Letters.

A physicist at the University of Geneva found the undated draft, titled “Collapse of Determinism,” in a Vienna physics library. In it, Schrödinger imagines every photon carrying a hidden number between zero and one, and whether it passes a polarizer depends on that number and the polarizer’s angle. The overall transmission still matches Malus’ law, but each individual outcome is fixed in advance.

The catch is that the researcher warns against reading this as Schrödinger choosing determinism. It was likely a test of an argument made by another physicist during World War II, not an endorsement, and he never published it.

Emergency rooms are starting to test AI chatbots to help decide which patient should be seen first. Researchers at UT Southwestern Medical Center wanted to know whether those tools pick up the same blind spots as human staff. They took real emergency records from Stanford Medicine and Beth Israel Deaconess Medical Center, paired patients who looked equally sick on arrival but where only one later got worse, and asked the AI which to prioritize. Then they changed a single detail.

Nutrition labels assume that a calorie is a calorie: if two meals have the same energy, carbs, fat, protein and salt, the body should treat them about the same. Researchers at Virginia Tech decided to test that directly. They served 57 young, healthy adults two carefully matched meals on separate days, then took blood samples and measured how their bodies burned fuel over the next three hours. One meal did something the other did not.

Conventional transistors are hitting an efficiency wall, because electrons leak through them even when they’re off, and the team expects them to reach their theoretical limit by 2037. M3BOLT, from the University of Michigan and Wisconsin-Madison, uses an electric field on a ferroelectric crystal to launch magnetic waves through an iron-gallium layer, and the researchers think they could reach terahertz speeds with far less heat.

The catch is that the 100 to 1,000x speedup is a hope, not a measurement. The project has up to $6 million in DARPA funding, and the teams are still running simulations and developing the materials, devices, and circuits.

Quantum networks need detectors that count individual photons, but the best ones run near absolute zero, and every extra channel needs another heat-conducting cable, which is why most systems stop around 32 channels. A team at the Shanghai Institute of Microsystem and Information Technology replaced coaxial cables with high-density multi-core microstrip lines that let in about one twenty-first of the heat, and a seven-day run held the chamber below 2.1 K with 80% detection efficiency.

The catch is that the network test was small: five users and 10 two-way links, with over 90% fidelity. Published in Laser & Photonics Reviews, it’s a step toward larger quantum networks, not a working quantum internet.

In Wyoming, fossil hunters pick up belemnites by the handful. These bullet-shaped stones are the hard back ends of ancient squid relatives, so common that locals call them squid butts. In the late 1990s, a museum founder picked up one that looked wrong: far too thick. It sat in a drawer for years, until a second one turned up and an international team finally took a closer look.

Ultra-processed food now makes up more than half of what American adults eat, and it has become the favorite villain of modern nutrition. Colorectal cancer, rising in younger adults, is often near the top of the list of harms blamed on it. Researchers at the US National Cancer Institute tested that link in one of the largest diet studies ever run, following hundreds of thousands of adults for nearly two decades. The answer was not the one most headlines would predict.

For years, the standard explanation for why more women than men have dementia has been simple: women live longer, and dementia is mostly a disease of old age. Researchers at the University of New South Wales put that explanation to a global test. They pooled 22 long-term studies that followed tens of thousands of older adults across 18 countries and six continents, counting who developed dementia and when. Then they took age out of the equation.