A Brief History of Time
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A Brief History of Time: From the Big Bang to Black Holes is a book on cosmology by the physicist Stephen Hawking, first published in 1988.
First edition
Ptolemy's Earth-centric model about the location of the planets, stars, and Sun
The expansion of the universe since the Big Bang
The Big Bang and the evolution of the universe
Turtles all the way down
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"Turtles all the way down" is an expression of the problem of infinite regress. The saying alludes to the mythological idea of a World Turtle that supports a flat Earth on its back. It suggests that t
A Brief History of Time
…the back of a giant tortoise." The scientist asked what the tortoise was standing on. She replied, "You're very clever young man, very clever. But it's turtles all the way down!" Hawking goes on to explain why we know better. He discusses the history of astronomy, starting with Aristotle's conclusions about a spherical Earth…
The saying holds that the world is supported by an infinite stack of increasingly larger turtles.
Four World Elephants resting on a World Turtle
William James