Einstein’s theory of relativity has explained the universe for more than a century. But under certain conditions, cracks begin to appear. Physicists have identified a gap Einstein never had the tools ...

For several years, an innovative, California-based launch company named Relativity Space has been the darling of investors and media. Relativity promised to disrupt launch by taking a somewhat niche ...

New research suggests Einstein's general relativity explains the rarity of planets orbiting two suns. In tight binary systems, relativistic effects cause orbital resonances that destabilize planets, ...