Captain Marvel: 12 Rumours That Were Utter Bull
6. Carol Gets Trapped In The Quantum Realm At The End
The Rumour: Ever since Avengers: Infinity War, fans have anguished about the location of Captain Marvel and exactly what she was up to while Thanos launched his crusade on Earth.
Some assumed that Carol was in some form of hibernation which was only interrupted by Fury's pager call, though many came to believe that she had somehow become trapped in the quantum realm by the end of her solo movie.
This would presumably lead to her bumping into Scott Lang (Paul Rudd) either in this film's post-credits scene or at the start of Endgame, and together they'd find a way out.
The Truth: Again, the quantum realm is pretty much a non-entity as far as this movie is concerned, and that's probably for the best. Plus, wouldn't it seem a bit lazy to have two Avengers trapped in the quantum realm together?
Still, there isn't a huge effort made to explain Carol's absence from Earth beyond her simply exploring the galaxies and presumably helping whoever needs to be helped.
Given the size of the known universe, it's a decent enough hand-waive, even if some fans were probably expecting a more substantial explanation.