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The root of today’s quantum revolution was John Stewart Bell’s 1964 theorem showing that quantum mechanics really permits instantaneous connections between far-apart locations.

Other diseases with long-term symptoms can help us understand how COVID can affect us long after the virus itself is gone.

These ultrabright flashes have recently been tracked for days, upending ideas about the cataclysms that create them.

Animals sculpt the optical properties of their tissues at the nanoscale to give themselves “structural colors.” New work is piecing together how they do it.

Originally devised as a rigorous means of counting holes, homology provides a scaffolding for mathematical ideas, allowing for a new way to analyze the shapes within data.

An enigmatic connection between the forces of nature is allowing physicists to explore gravity’s quantum side.

The thorny thought experiment has been turned into a real experiment — one that physicists use to probe the physics of information.

Despite finding no specific examples, researchers have proved the existence of a pervasive kind of prime number so delicate that changing any of its infinite digits renders it composite.

The zoo of spontaneously emerging particlelike entities known as quasiparticles has grown quickly and become more and more exotic. Here are a few of the most curious and potentially useful examples.