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A Century Later, New Math Smooths Out General Relativity
Mathematicians prove a theorem that illuminates the geometry of universes with tiny amounts of mass.
Math Proof Draws New Boundaries Around Black Hole Formation
For a half century, mathematicians have tried to define the exact circumstances under which a black hole is destined to exist. A new proof shows how a cube can help answer the question.
The Physicist Who’s Challenging the Quantum Orthodoxy
For decades, physicists have struggled to develop a quantum theory of gravity. But what if gravity — and space-time — are fundamentally classical?
An Enormous Gravity ‘Hum’ Moves Through the Universe
Astronomers have found a background din of exceptionally long-wavelength gravitational waves pervading the cosmos.
The Physicist Who Glues Together Universes
Renate Loll has helped pioneer a radically new approach to quantum gravity. She assumes that the fabric of space-time is a blend of all possible fabrics, and she has developed the computational tools needed to calculate the far-reaching implications of that assumption.
Are There Reasons to Believe in a Multiverse?
Several areas of physics suggest reasons to think that unobservable universes with different natural laws could lie beyond ours. The theoretical physicist David Kaplan talks with Steven Strogatz about the mysteries that a multiverse would solve.
New Proof Finds the ‘Ultimate Instability’ in a Solar System Model
For the first time, mathematicians have proved that planetary orbits in a solar system will always be unstable.
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.