Table of Contents: “...Introduction -- What is a Scientific Theory? -- The First Cosmological Revolution of the 20th Century -- The Theory of General Relativity and Its Main Solutions -- The Hubble-Lemaître Law and the Universe Expansion -- The Big Bang Theory -- Towards...”

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Table of Contents: “... at the Beginning of the Twentieth Century -- Chapter 6: The Andromeda Nebula and the Great Island-Universe Debate -- Chapter 7: Edwin Hubble, an Infinite Universe, and the Classification of Galaxies -- Chapter 8: Andromeda, Galactic Redshift, and the Big Bang Theory...”

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