How Our Reality May Be a Sum of All Possible Realities
Richard Feynman’s path integral is both a powerful prediction machine and a philosophy about how the world is. But physicists are still struggling to figure out how to use it, and what it means.
Mathematicians Eliminate Long-Standing Threat to Knot Conjecture
A new proof shows that a knot some thought would contradict the famed slice-ribbon conjecture doesn’t.
Theory has it that “Population III” stars brought light to the cosmos. The James Webb Space Telescope may have just glimpsed them.
How Quantum Physicists ‘Flipped Time’ (and How They Didn’t)
Two teams have made photons act as if time were simultaneously flowing in two directions. The experiments demonstrate a way to potentially boost the performance of quantum devices.
The Cause of Depression Is Probably Not What You Think
Depression has often been blamed on low levels of serotonin in the brain. That answer is insufficient, but alternatives are coming into view and changing our understanding of the disease.
The Computer Scientist Who Finds Life Lessons in Games
In Shang-Hua Teng’s work, theoretical and practical questions have long been intertwined. Now he’s turning his focus to the impractical.
Mathematicians Find an Infinity of Possible Black Hole Shapes
In three-dimensional space, the surface of a black hole must be a sphere. But a new result shows that in higher dimensions, an infinite number of configurations are possible.