Anonymous asked in Science & MathematicsAstronomy & Space · 3 years ago

Who first proposed that the universe is expanding?

A. Galileo

B. Kepler

C. Copernicus

D. Hubble

9 Answers

  • 3 years ago

    None of them.

    However, if this is from an American book, the answer will be Hubble.

    Father Georges Lemaitre was working with Hubble when they noticed all galaxies appeared to be moving away from each other. The first explanation that was tried was that of an explosion (1927).

    However, Georges Lemaitre built a mathematical model to show that space itself had to change in the presence of mass. Either it had to contract or to expand.

    Given the observations he had made with Hubble, the easy conclusion was "expand".

    Einstein had also built a mathematical model for the behaviour of space, but he had added a "cosmological constant" to prevent the model from predicting an expansion (Einstein wanted space to be static).

    In the early 1930s, Father Lemaitre had a discussion with Einstein and, at the end, they both agreed that space was expanding.

    It is Lemaitre's mathematical model that later became the Big Bang theory.

    However, all it says is that SPACE expands. We do not know that the universe expands.

    There are some geometrical configurations under which the universe does not need to expand even if it is already "full" of expanding space.

  • paul h
    Lv 7
    3 years ago

    E...none of the above. The first to propose an expanding universe was a Russian scientist named Alexander Friedmann in 1922. 5+ years before Lemaitre or Hubble.

    And one might assert that even much earlier, the Bible infers an expanding universe in various verses describing God "stretching out the Heavens.

    "Friedmann in 1922 introduced the idea of an expanding universe that contained moving matter; Belgian astronomer Georges Lemaître would later independently reach the same conclusion in 1927.[4]"

  • KennyB
    Lv 7
    3 years ago

    In 1927, the year he got his PhD from MIT, George LeMaitre proposed this theory, in which he stated that the expanding universe was the same in all directions.

    In 1929 Edwin Hubble measured the redshifts of a number of distant galaxies. When he plotted redshift against relative distance, he found that the redshift of distant galaxies increased as a linear function of their distance. The only explanation for this observation is that the universe was expanding.

    Given your list then, the only answer is D but the concept of an expanding universe predates Hubble.

  • 3 years ago

    Well, ..., the closest answer in your solution set is D. Edwin Hubble.

    However, as other's have pointed out, Georges Lemaitre was the first to propose it.

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  • 3 years ago

    I believe that it was the Hubble

  • Al
    Lv 7
    3 years ago

    Can't figure out how to use or or eh?

  • 3 years ago

    charles darwin

  • Anonymous
    3 years ago

    Hmm! Not sure, probably C or D

  • 3 years ago


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