This just in: Robert Redford, Rooney Mara, and Jason Segel are headed to Rhode Island to start shooting a sci-fi love story called “The Discovery.’’ Charlie McDowell, whose credits include “The One I Love,’’ is directing and also co-wrote the script with Justin Lader. (They also co-wrote “The One I Love.’’) In the film, which will begin shooting this month, the 79-year-old Redford plays a scientist who’s proven the existence of an afterlife, and Mara plays a woman who falls in love with the scientist’s son, played by Segel. Redford last filmed in Rhode Island while making 1974’s “The Great Gatsby,’’ which went on to win Academy Awards for best costume design and best music. Last time Segel filmed around here — 2013’s “Sex Tape’’ with Cameron Diaz — we learned that the actor’s grandfather founded Mr. Sid’s in Newton Centre.