The merger of Compass and Anywhere Real Estate would create a company valued at about $10 billion, with a network of roughly 340,000 real estate professionals across 120 countries and territories.

Two of the nation’s largest real estate brokerages are one step closer to combining, creating a behemoth nearly three times as large as their closest competitor. The deal is expected to close on ...

The original version of this story appeared in Quanta Magazine. All of modern mathematics is built on the foundation of set theory, the study of how to organize abstract collections of objects. But in ...