The Erdős-Bacon number is defined as the sum of the number of onscreen filmmaking collaborations it takes to connect a person to actor Kevin Bacon, and the number of academic publishing collaborations it takes to reach mathematician Paul Erdős. According to a recent article, “Natalie Portman has a Erdős-Bacon number of seven, as does Colin Firth, and Danica McKellar’s number is six. The actor with the lowest number is apparently Albert M. Chan, who appeared with Bacon in Patriots Day. His number is four.”

Albert co-authored a peer-reviewed paper on OFDM with Carl-Erik Sundberg, who in turn co-authored a paper with Harold Shapiro on invariant subspaces in Bergman spaces, who in turn co-authored a paper with Paul Erdős on large and small subspaces of Hilbert space, giving Albert an Erdős number of 3.

Most recently, Albert was cast alongside Kevin Bacon in Patriots Day, giving him a Bacon number of 1.

Patriots Day, about the 2013 Boston Marathon Bombings, opens in Boston, NY, and LA on December 21 and everywhere else on January 13.