Punxsutawney Phil saw his shadow this morning, and according to legend that means we're in for six more weeks of winter. But Phil has a motley track record. At 30% accuracy, he doesn't even beat the flip of coin; he's more like a drunk at a poker table: You could make money simply by betting against him. But that porky rodent has his moments, none better than the inspiring film Groundhog Day.When it was released in 1993, the movie was dismissed as decent but forgettable. But it has bloomed with age, going on to make several "Greatest of All Time" lists (Funniest, Best Screenplay, and others) and earning a firm cultural currency. Losing baseball pitchers and Middle East negotiators alike have likened their sorry plights to living inside the movie. Big brains have picked up on Groundhog Day as well: Religious figures, scientists, and economists have all turned it into a teaching lesson-seriously, and for good reasons.Before getting to the meat of those interpretations, let's recap the movie. The main character, played by Bill Murray, is Phil Conners, a sourpuss Pittsburgh anchorman covering Groundhog Day in Punxsutawney, Pennsylvania. He and his crew are eager to get back home to Pittsburgh after the groundhog ceremony wraps, but the roads are snowed over. So instead they stay at a hotel in town.Then things get weird. The next morning, Phil wakes not to the next day, but the day before: Groundhog Day. He remembers everything, but no one else does. And the day unfolds just as it did; day after day, the same thing happens. Angry and bored, Phil at first amuses himself by using his supernatural knowledge to spy on the town burghers and bed its women. Only one person remains immune to his charm: His co-worker Rita. With her, Phil gets ignored, laughed at, and slapped. So eventually he lets go, diverting himself elsewhere, learning French and how to play the piano. Eventually, he begins helping the town's residents with their myriad daily problems. Another date with Rita comes up. At various times, nearly the entire town ambles up to thank him for his good works during the day. The show wins Rita over, and they go back to the hotel. Next morning, he wakes up with Rita beside him. And at last, the calendar has turned to the next day.It's a charming, big-hearted story whose major features-time travel and redemption-scream for interpretation. Science, religion, and economics have each provided one:Physics"For physicists, film always resonates as a way to explain time," says Peter Galison, a science historian at Harvard, a certified MacArthur Grant genius, and a filmmaker himself. "They always talk about running film in reverse. Meanwhile, in every stage of film history, filmmakers have played with time's conventions."Some theories in physics have been explicitly inspired by movies. With Groundhog Day, Galison notes that the idea of a single, endlessly repeating day neatly parallels current cutting edge thinking in physics. According to the "Cyclic Universe" theory propounded by string theorists at Cambridge and Princeton, the specific tuning of our universe-from the number of spatial dimensions that we see to the charge of an electron-is merely the product of a universe caught in an eternal, oscillating cycle. It begins with a big bang. The universe expands for a time, but then eventually contracts into a "big crunch," sparking yet another, do-over big bang-the same day, all over again, with subtle but crucial differences.EconomicsEconomists, meanwhile, have argued that Groundhog Day highlights the unbridgeable gulf between classic economics and real-world behavior. They point out that the first time Phil Conners lives out Groundhog Day, he knows nothing about how events will unfold, and acts accordingly-self centered, short sighted and rash. But by the time Conners lives out his last Groundhog Day, he has perfect knowledge of how everyone around him will behave. He acts accordingly-maximizing his happiness and the happiness of those around him. The metaphor gets pretty loose, but in this interpretation, Phil's last day is analogous to classical economics, where people act with perfect knowledge and rationality. But we never know what's going to happen in the future, or exactly what people will do, so instead, we live more like Phil does on his first Groundhog Day: We muddle through using half-baked assumptions and habitual attitudes.BuddhismThe screenwriter Danny Rubin has admitted that he never intended all of Groundhog Day's symbolic interpretations, but priests and rabbis have assumed that the film was intended to carry a religious moral because Phil Conners escapes the time loop (and his purgatorial boredom) when he gives in to selflessness and dedicates himself to helping others. But Buddhism offers the most exacting interpretation.The most obvious aspect is that Phil, reliving each day, is enacting something like the cycle of constant rebirth posited by Mahayana Buddhism. But it goes deeper than that. A hard-core Buddhist interpretation holds that Phil's great revelation isn't eventually helping others, but realizing that he's doomed to repeat the day he's living. "Phil's trapped in his own mind," says Angela Zito, a professor of religion and anthropology at NYU. "That's a metaphor for what every one of us goes through."Interpretations of Buddhism vary, but a popular rendition is that life is suffering-the endless cycle of being lashed by desires and then disappointed by what they yield. It repeats endlessly because we don't know a way out. The only solution is to let go of desire-like Phil does, once he's had his fill of the carnal pleasures of Punxsutawney's women and commits himself to doing good without any expectation of benefit. "What Phil slowly sees is that he isn't just embedded in the day he's living. He's actually making it," says Zito, who's shown the movie to students for several years to illustrate various Buddhist precepts. "But after he realizes his actions are making a difference, he soon realizes that they don't get him what he wants. Eventually he lets go, and that's when the day finally changes." Of course, it's not exactly Buddhist that Phil's change of heart is rewarded with sex, but hey, that's Hollywood.GROUNDHOG DAY EVENTSGalison is introducing a screening of Groundhog Day in Boston on Groundhog Day, Monday, February 2.Zito is speaking in Cambridge on Groundhog Day as well. She's discussing the film with its screenwriter, Danny Rubin.