(Since a full rotation brings every point on the triangle back to where it started, mathematicians stop counting rotations past 360 degrees.) These symmetries are discrete: They form a set of distinct transformations that have to be applied in separate, unconnected steps. But you can also study continuous symmetries. It doesn’t matter, for instance, if… Continue reading What Are Lie Groups? | Quanta Magazine
The Students Who Disappear Before They Count
U.S. community colleges are finally rebounding from the pandemic, though they are still not back to pre-2020 enrollment levels. Only about one-quarter of colleges have recovered their full student body. But there’s a more troubling loss that institutions rarely measure: the new applicants who leave before the “census date,” the point a few weeks into… Continue reading The Students Who Disappear Before They Count
Diet and Exercise Might Slow Alzheimer’s—But Is That Just False Hope?
This article is part of “Innovations In: Alzheimer’s Disease” an editorially independent special report that was produced with financial support from Eisai. When Juli comes home after work, her husband doesn’t regale her with stories about his photography business the way he once did. Instead he proudly shows her a pill container emptied of the… Continue reading Diet and Exercise Might Slow Alzheimer’s—But Is That Just False Hope?
Carrying On: British Jews Face Growing Antisemitism With Resolve
Joseph Cohen had worked for an organization in Britain devoted to encouraging Jewish-Muslim dialogue and combating antisemitism. But following Hamas’ Oct. 7, 2023, attack on Israeli civilians and then the bombing and destruction of Gaza, the rising tide of sometimes violent antisemitism made him feel he no longer belonged in his native land. “I would… Continue reading Carrying On: British Jews Face Growing Antisemitism With Resolve
‘Reverse Mathematics’ Illuminates Why Hard Problems Are Hard
When it comes to hard problems, computer scientists seem to be stuck. Consider, for example, the notorious problem of finding the shortest round-trip route that passes through every city on a map exactly once. All known methods for solving this “traveling salesperson problem” are painfully slow on maps with many cities, and researchers suspect there’s… Continue reading ‘Reverse Mathematics’ Illuminates Why Hard Problems Are Hard
China Is Worried About AI Job Losses
In Shanghai, jobless young professionals are paying $5 a day to sit beneath fluorescent lights at the aptly named Pretend to Work Co., one of many faux offices across the city that offer Wi-Fi, coffee, and the illusion of employment. Likely no more than a few blocks away, rural migrant workers sleep in shifts in… Continue reading China Is Worried About AI Job Losses
Can Dogs, Cats and Other Pets Truly Improve Your Health?
September 16, 2025 4 min read Can Dogs, Cats and Other Pets Truly Improve Your Health? Pets can improve your health—but only if you have a strong relationship with the animals By Lydia Denworth edited by Josh Fischman We got our first dog when my oldest son was 10. A friend who was a teacher… Continue reading Can Dogs, Cats and Other Pets Truly Improve Your Health?
Particle Physicists Detect ‘Magic’ at the Large Hadron Collider
Quantum information researchers began looking for ways to generate and enhance magic in quantum systems. This caught the attention of a few particle physicists — including Martin and Chris White — who wondered how magic appears in systems of elementary particles. “We thought, the LHC is a quantum system. Top quarks are a quantum system.… Continue reading Particle Physicists Detect ‘Magic’ at the Large Hadron Collider
The Problem with Billionaire Science
September 16, 2025 3 min read The Problem with Billionaire Science Science may need to increasingly rely on wealthy patrons, but privately funded projects don’t always pan out By David M. Ewalt Scientific American, October 2025 A poster-size version of the front page of the very first issue of this magazine hangs in the lobby… Continue reading The Problem with Billionaire Science
The Sword of St. Michael (and More Weird Questions)
Podcast: Download MYS393: It’s our annual Thanksgiving Weird Questions episode, and this time Cy Kellett is asking Jimmy Akin questions about whether the Holy Spirit has chromosomes, what sacraments angels can perform (if any), whether Zoroaster was a savior before Jesus, and what to make of the sword of St. Michael. Get all new episodes… Continue reading The Sword of St. Michael (and More Weird Questions)