A new study has presented significant challenges to one of cosmology's most fundamental assumptions, suggesting that dark energy — the mysterious force believed to make up roughly 70% of the universe and drive its accelerating expansion — may not exist as currently understood. Researchers found evidence that the universe is asymmetric, or "lopsided," undermining the FLRW framework (the mathematical model underpinning nearly all standard cosmological analyses, which assumes the universe looks the same in all directions). The findings, which also suggest that signals from Type Ia supernovae long used as key evidence for dark energy may be directional illusions caused by Earth's particular location in a region of large-scale galactic motion, could point toward a fundamental rethinking of the standard model of cosmology if independently confirmed.