quanta magazine

The Mysterious ‘Dark’ Energy That Permeates the Universe Is Slowly Eroding

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Beyond DESI, a slew of new instruments are coming online in the coming years, including the 8.4-meter Vera Rubin Observatory in Chile, NASA’s Nancy Grace Roman Space Telescope, and the European Space Agency’s Euclid mission. “Our data in cosmology has made enormous leaps over the last 25 years, and it’s about to make bigger leaps,” … Read more

The Quest to Map the Inside of the Proton

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“How are matter and energy distributed?” asked Peter Schweitzer, a theoretical physicist at the University of Connecticut. “We don’t know.” Schweitzer has spent most of his career thinking about the gravitational side of the proton. Specifically, he’s interested in a matrix of properties of the proton called the energy-momentum tensor. “The energy-momentum tensor knows everything … Read more

A Popular Alien-Hunting Technique Is Increasingly in Doubt

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The third factor is the probability of a lifeless planet producing the observed signal—an equally serious challenge, researchers now realize, that’s tangled up in the problem of unconceived abiotic alternatives. “That’s the probability that we argue you can’t fill in responsibly,” Vickers said. “It could almost range from anything from zero to 1.” Consider the … Read more

The Brain Region That Controls Movement Also Guides Feelings

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The original version of this story appeared in Quanta Magazine. In recent decades, neuroscience has seen some stunning advances, and yet a critical part of the brain remains a mystery. I am referring to the cerebellum, so named for the Latin for “little brain,” which is situated like a bun at the back of the … Read more

Large Language Models’ Emergent Abilities Are a Mirage

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The original version of this story appeared in Quanta Magazine. Two years ago, in a project called the Beyond the Imitation Game benchmark, or BIG-bench, 450 researchers compiled a list of 204 tasks designed to test the capabilities of large language models, which power chatbots like ChatGPT. On most tasks, performance improved predictably and smoothly … Read more

Never-Repeating Patterns of Tiles Can Safeguard Quantum Information

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This extreme fragility might make quantum computing sound hopeless. But in 1995, the applied mathematician Peter Shor discovered a clever way to store quantum information. His encoding had two key properties. First, it could tolerate errors that only affected individual qubits. Second, it came with a procedure for correcting errors as they occurred, preventing them … Read more

Selective Forgetting Can Help AI Learn Better

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The original version of this story appeared in Quanta Magazine. A team of computer scientists has created a nimbler, more flexible type of machine learning model. The trick: It must periodically forget what it knows. And while this new approach won’t displace the huge models that undergird the biggest apps, it could reveal more about … Read more

This Is What Your Brain Does When You’re Not Doing Anything

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The original version of this story appeared in Quanta Magazine. Whenever you’re actively performing a task—say, lifting weights at the gym or taking a hard exam—the parts of your brain required to carry it out become “active” when neurons step up their electrical activity. But is your brain active even when you’re zoning out on … Read more

There’s a New Theory About Where Dark Matter Is Hiding

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But there may be opportunities to indirectly spot the signatures of those gravitons. One strategy Vafa and his collaborators are pursuing draws on large-scale cosmological surveys that chart the distribution of galaxies and matter. In those distributions, there might be “small differences in clustering behavior,” Obied said, that would signal the presence of dark gravitons. … Read more