Solution: The wrinkle in "A Wrinkle in Time" and the Cosmic Cube in Marvel Comics, for two - NYT Crossword

Good on these constructors for getting to this entry first, in plural or singular form, because it’s a really neat concept and belongs in a cool themed puzzle one day. TESSERACTS are representations of a fourth dimension — they are to cubes what cubes are to two-dimensional squares, or to spheres what spheres are to circles. In “A Wrinkle in Time,” a book she wrote in 1962, the author Madeleine L’Engle considered tesseracts to be quite similar to wormholes; Nathan ROSEN and Albert Einstein posited wormholes decades earlier, in 1935.