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Studying the structure of existing friendships in your community can help you forge the best connections when forming a new circle of friends.

How many colors do you need to color an infinite plane so that no points 1 unit apart are the same color?

Scientists seek a single description of reality. But modern physics allows for many different descriptions, many equivalent to one another, connected through a vast landscape of mathematical possibility.

What does John Nash’s game theory equilibrium concept look like in Rock-Paper-Scissors?

Gravitational waves have opened up new ways to test the properties of black holes — and Einstein’s theory of gravity along with them.

The theoretical physicist Joe Polchinski, who died Feb. 2, left a tremendous professional and personal legacy, says a friend and collaborator.

Simple math shows how widespread vaccination can disrupt the exponential spread of disease and prevent epidemics.

For decades, physicists have struggled to create a quantum theory of gravity. Now an approach that dates to the 1970s is attracting newfound attention.

Triangles fit effortlessly together, as do squares. When it comes to pentagons, what gives?