The universe is commonly defined as the totality of existence, including planets, stars, galaxies, the contents of intergalactic space, and all matter and energy. Definitions and usage vary and similar terms include the cosmos, the world and nature.
Scientific observation of earlier stages in the development of the universe, which can be seen at great distances, suggests that the universe has been governed by the same physical laws and constants throughout most of its extent and history. The universe is believed to be at least 93 billion light years in diameter and has existed for about 13.7 billion years, since it was created by the Big Bang.
There are various multiverse hypotheses, in which physicists have suggested that the universe might be one among many universes that likewise exist. The farthest distance that it is theoretically possible for humans to see is described as the observable universe. Observations have shown that the universe appears to be expanding at an accelerating rate, and a number of models have arisen to predict its ultimate fate.
Read more about Universe: Etymology, Synonyms and Definitions, Size, Age, Contents, Structure, and Laws, Historical Models, Theoretical Models, Shape of The Universe
Famous quotes containing the word universe:
“Since the Greeks, Western man has believed that Being, all Being, is intelligible, that there is a reason for everything ... and that the cosmos is, finally, intelligible. The Oriental, on the other hand, has accepted his existence within a universe that would appear to be meaningless, to the rational Western mind, and has lived with this meaninglessness. Hence the artistic form that seems natural to the Oriental is one that is just as formless or formal, as irrational, as life itself.”
—William Barrett (b. 1913)
“What the hell is nostalgia doing in a science-fiction film? With the whole universe and all the future to play in, Lucas took his marvelous toys and crawled under the fringed cloth on the parlor table, back into a nice safe hideyhole, along with Flash Gordon and the Cowardly Lion and Luck Skywalker and the Flying Aces and the Hitler Jugend. If there’s a message there, I don’t think I want to hear it.”
—Ursula K. Le Guin (b. 1929)
“... if we take the universe of ‘fitting,’ countless coats ‘fit’ backs, and countless boots ‘fit’ feet, on which they are not practically fitted; countless stones ‘fit’ gaps in walls into which no one seeks to fit them actually. In the same way countless opinions ‘fit’ realities, and countless truths are valid, tho no thinker ever thinks them.”
—William James (1842–1910)