Director James Cameron says he has ‘scientific’ proof that Leonardo DiCaprio’s Jack would never have survived in ‘Titanic’

His heart wouldn’t have gone on.

Leonardo DiCaprio’s Jack had to die in “Titanic” — and science can prove it, the director of the 1997 blockbuster said in a recent interview.

James Cameron told the Toronto Sun that he wants fans of the epic love story to understand “once and for all” that Jack Dawson needed to die in the film after his much-debated decision not to climb onto the floating door that saved the life of his beloved Rose (Kate Winslet) after the ship went down.

Jack would not have lived even if he had joined Rose on the makeshift raft, Cameron said, hoping to shut down the many fan theories circling the pop culture stratosphere for the past quarter-century.

“We have since done a thorough forensic analysis with a hypothermia expert who reproduced the raft from the movie, and we’re going to do a little special on it that comes out in February,” when a 4K re-release of the film is set to hit theaters, Cameron said.

“Only one could survive.”

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“MythBusters” once found in a 2012 episode that Jack and Rose could have fit on the door and survived the frigid water.

But Cameron said the new analysis — which involved covering two stunt performers in sensors and placing them in ice water to test “through a variety of methods” if they both could have lived — came to a different conclusion.

“The answer was, there was no way they both could have survived,” said the Academy Award-winning filmmaker.

The box office phenomenon returns to the big screen on Valentine’s Day, while “this little science project is going to run on National Geographic,” Cameron said.

“And maybe, maybe after 25 years, I don’t have to deal with this anymore,” he laughed.

But science aside, storytelling dicated Jack’s demise, the director said.

“It’s like ‘Romeo and Juliet,’” Cameron explained. “It’s a movie about love, sacrifice and mortality.”