Big crunch

Definition

The Big Crunch is a theoretical scenario in which the expansion of the universe eventually reverses, causing it to collapse back into a singularity. This hypothesis contrasts with the idea of an ever-expanding universe and suggests a cyclic model of cosmic evolution.

5 Must Know Facts For Your Next Test

1. The Big Crunch suggests that gravitational forces will eventually overcome the expansion caused by the Big Bang.
2. It implies that all matter and energy in the universe will compress into an extremely hot and dense state.
3. This theory is contingent on the density of matter in the universe being high enough to halt its expansion.
4. Observational data, such as measurements of cosmic microwave background radiation, are used to evaluate this possibility.
5. The Big Crunch is one possible outcome among others like the Big Freeze or Big Rip.

Review Questions

• What conditions must be met for the Big Crunch to occur?
• How does the concept of the Big Crunch contrast with an ever-expanding universe?
• What observational evidence would support or refute the Big Crunch theory?

Related terms

Big Bang: A scientific theory describing how the universe expanded from a very high-density and high-temperature initial state.

Cosmic Microwave Background Radiation: Electromagnetic radiation left over from an early stage of the universe, also known as relic radiation.

Big Rip: A hypothetical cosmological model where dark energy causes continuous acceleration leading to a future tearing apart of all structures in the universe.