Exploring Astronomy Photography Of Outer Space Universe

• Broadest definition: reality and probability
The broadest definition of the universe is found in De divisione naturae by the medieval philosopher and theologian Johannes Scotus Eriugena, who defined it as simply everything: everything that is created and everything that is not created.
• Definition as reality
More customarily, the universe is defined as everything that exists, (has existed, and will exist). According to our current understanding, the universe consists of three principles: spacetime, forms of energy, including momentum and matter, and the physical laws that relate them.