big crunch

The "big crunch" is a hypothetical cosmological event where all matter in the universe collapses into a singularity. This is considered a possible fate for the universe if its matter density is sufficiently high.1

This concept is contrasted with the "big bang" model, which is the currently accepted cosmological model describing the universe's origin and evolution. The big bang theory posits that the universe began about 13.8 billion years ago in an extremely dense and hot state and has been expanding ever since.234

While the big bang model is widely accepted, astronomers have explored various possibilities for the universe's ultimate fate. One scenario, the "big crunch," suggests a reversal of expansion leading to a collapse. However, current observations, particularly regarding dark energy, suggest a continued expansion, potentially leading to a "big chill" rather than a collapse.34