The Universe is defined as the summation of all particles and energy that exist and the space-time in which all events occur. Based on observations of the portion of the universe that is observable, physicists attempt to describe the whole of space-time, including all matter and energy and events which occur, as a single system corresponding to a mathematical model.

Big Bang Theory

  • Define
  • Evidence
  1. LeMaitre
  2. Hoyle elements form in stars
  3. Doppler Effect - Red shift
  4. Penzius and Wilson- Cosmic Background Radiation

Inflation Theory

Open-Closed Universe debate

  1. Entropy -
  2. Omega -
  3. Open -
  4. Closed -


Universe Website

NASA website