When Thanos snaps his fingers with the full might of the Infinity Gauntlet at the end of Avengers: Infinity War, annihilating half of all living creatures in existence, around 23 years have passed since Carol Danvers had her first adventure during Captain Marvel. In the MCU, Danvers was born around 1960, so how is it that the 29-year-old Brie Larson portrays the character in both timelines?

Part of the explanation probably has a lot to do with her being the most powerful character in the Marvel Cinematic Universe. After all, Captain America and Winter Soldier are both a century old when Infinity War happens and they still look great, so it’s not outlandish to think that Carol’s immense powers preserve her youth.

However, there’s also a very sciency (and spoilery) explanation as to why Danvers doesn’t age between Captain Marvel and Endgame, and it has a lot to do with the real-life physics behind Albert Einstein’s theory of special relativity.

Spoilers follow for Captain Marvel and Avengers: Endgame.

Captain Marvel
Carol Danvers unlocks her true potential in ‘Captain Marvel’.

Unlike Steve Rogers and Bucky Barnes, Carol Danvers never undergoes cryogenic freezing to stall her aging. (For what it’s worth, both super soldiers probably age at a slower rate than normal human beings anyway.) For Carol, who was imbued with the energy of the Space Stone following an explosion in 1989, her astronomical power levels grant her strength unlike anything we’ve ever seen before.

She could easily beat Hulk in an arm-wrestling match, and will probably be the one to soundly defeat Thanos in Endgame. But when Captain Marvel ends, she flies away at the speed of light to guide a ship full of Skrull refugees to a new home somewhere several galaxies away….