According to the "Standard Model" of cosmology, the Universe is 68% dark energy, 27% dark matter, 5% normal matter, and is 13.8 billion years old: as measured since the hot Big Bang. Recent observations from the James Webb Space Telescope (JWST), however, have found numerous galaxies that appear early, but look surprisingly grown-up. A new theory claims to solve this "early, grown-up galaxies" problem by changing the age of the Universe to 26.7 billion years old. Here's how scientists will decide.