Cosmic time

Cosmic time is a way of measuring time that applies to the entire universe, particularly in cosmology. It assumes a uniform flow of time since the Big Bang, approximately 13.8 billion years ago. Unlike local time, which can vary depending on gravity or velocity (as described by Einstein’s relativity), cosmic time offers a consistent frame of reference for understanding events in the universe’s history, like the formation of galaxies and stars. It helps scientists understand the age and evolution of the universe itself, providing a backdrop against which cosmic events can be compared.