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Quantum computers can’t selectively forget information. A new algorithm for multiplication shows a way around that problem.

One of the first quantum simulators has produced a puzzling phenomenon: a row of atoms that repeatedly pops back into place.

The same codes needed to thwart errors in quantum computers may also give the fabric of space-time its intrinsic robustness.

In a Paris lab, researchers have shown for the first time that quantum methods of transmitting information are superior to classical ones.

Urmila Mahadev spent eight years in graduate school solving one of the most basic questions in quantum computation: How do you know whether a quantum computer has done anything quantum at all?

18-year-old Ewin Tang has proven that classical computers can solve the “recommendation problem” nearly as fast as quantum computers. The result eliminates one of the best examples of quantum speedup.

What’s easy for a computer to do, and what’s almost impossible? Those questions form the core of computational complexity. We present a map of the landscape.

Computer scientists have been searching for years for a type of problem that a quantum computer can solve but that any possible future classical computer cannot. Now they’ve found one.

The mathematician Gil Kalai believes that quantum computers can’t possibly work, even in principle.