It's the viral theory about Avengers: Endgame that just won't die: Ant-Man defeats Thanos by shrinking down, climbing into his anus, and expanding again to full size, thus causing the Mad Titan to explode.

While this plot was never truly credible in the first place, the film's directors, Anthony and Joe Russo, have already denied that it will play out this way. However, this hasn't stopped fans -- and even cast and crew members -- from discussing it. Now, even astrophysicists are being brought into the debate to offer their perspective.

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Neil deGrasse Tyson, speaking on his podcast StarTalk with fellow astrophysicist Charles Liu and comedian Chuck Nice, was asked if he had heard about the fan theory. His immediate response was to not only call out its nastiness -- especially for involving Thanos's "powerful, evil poop" -- but to replace it with an idea that uses the same logic while being a lot less gross.

Why not put an expanding object into Thanos's innards, asked Tyson, instead of an expanding person? "Send some other quantum thing in there to do it," he insisted, meeting with general agreement from Liu and Nice.

Even stalwart defenders of the Thanus theory might have to concede. In Ant-Man and its sequel, Ant-Man and the Wasp, characters were often seen using the Pym Particle technology to shrink and expand all kinds of matter, not just human bodies. While there's no doubt the movie itself will steer clear of any version of this strategy, fans may want to adjust their own theories after hearing this one.

RELATED: Avengers: Endgame's Josh Brolin Reacts to 'Thanus Theory'

Directed by Anthony and Joe Russo, Avengers: Endgame stars Robert Downey Jr., Chris Evans, Mark Ruffalo, Chris Hemsworth, Scarlett Johansson, Jeremy Renner, Don Cheadle, Paul Rudd, Brie Larson, Karen Gillan, Danai Gurira, Benedict Wong, Jon Favreau and Bradley Cooper, with Gwyneth Paltrow and Josh Brolin. The film arrives April 26.

(via ComicBook.com)