A year ago, Natalie Portman was the hottest actress around. The “ Black Swan ” star was sweeping awards and earning the sine qua non of actor heat, the "Saturday Night Live" parody. She even survived an ill-timed dorky laugh. But Portman didn’t get to indulge in the main perk that comes from winning an Oscar — booking a big, prestigious movie. Portman was five months pregnant when she accepted the golden statuette last February, and pretty much stopped working afterward so she and costar/choreographer Benjamin Millipied could have their son, Aleph, who was born in June. She hasn’t worked since. (Portman could be seen in several movies last spring — “Your Highness” and “Thor” — but she shot those before her pregnancy.) Could Portman soon be coming out of her baby-induced hiatus? According to a person briefed on the project who was not authorized to talk about it publicly, the actress has been courted by Lana and Andy Wachowski to star in “ Jupiter Ascending ,” the science-