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Two mathematicians have proved that two different infinities are equal in size, settling a long-standing question. Their proof rests on a surprising link between the sizes of infinities and the complexity of mathematical theories.

What can the mathematical genius Srinivasa Ramanujan teach us about number theory through mathematical structures involving infinity?

Insights from the mathematical genius Srinivasa Ramanujan give us a number of ways to explore the infinite.

Hilbert’s Hotel, an incredibly thin triangle and an elliptical pool table help us test the concept of infinity in the physical world.

Three puzzles test whether the concept of infinity has purchase in the physical world.

A surprising new proof is helping to connect the mathematics of infinity to the physical world.

To determine the nature of infinity, mathematicians face a choice between two new logical axioms. What they decide could help shape the future of mathematical truth.