Cosmic filaments set first limits on dark matter decay into gravitons

Across the vast filamentary scaffolding of the cosmos, researchers have found a new way to listen for the silence of dark matter — specifically, whether it quietly dissolves into gravitons, the hypothetical carriers of gravity. By reading the shape and density of the universe's largest structures, scientists have placed the first observational boundaries on a decay process that no earthly detector could hope to catch. It is a reminder that the universe itself is the oldest and most patient laboratory we have, and that learning to read its records is its own form of discovery.