Who First Conceived the Idea of the Cosmological Principle?

AI Thread Summary
The discussion centers on the origins of the cosmological principle, which posits that the universe's matter distribution is homogeneous and isotropic. The term "cosmological principle" was first used by astrophysicist Edward A. Milne, but its conceptual roots can be traced back to Newton's "Principia Mathematica." Participants also mention Einstein's cup of tea analogy and suggest Copernicus as a foundational figure in cosmological thought. There is some debate over whether Friedmann or Lemaitre contributed significantly to the idea. Overall, the conversation highlights the complexity of attributing the cosmological principle to a single individual.
yazanhomsi
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Good day all,

A question that I haven't really found the answer for yet: "Whom did first come up with the idea of the cosmological principle?"
I almost looked everywhere for the answer but still cannot find it. Was it Friedmann or Lemaitre? Or was it some other great physicist? But there should be someone who first came up with the notion that the distribution of all matter in the universe is homogeneous and isotropic.

Thank you!
 
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The actual phrase 'cosmological principle' appears to have been first used by the astrophysicist Edward A. Milne.
Conceptually it can be traced to Newton's Principia Mathematica.
 
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rootone said:
The actual phrase 'cosmological principle' appears to have been first used by the astrophysicist Edward A. Milne.
Conceptually it can be traced to Newton's Principia Mathematica.

What about Einstein and the cup of tea analogy of the universe? I read it in multiple of books. Isn't he the first one to come up with it?
 
In an indirect way, I credit Copernicus as founder of the cosmological principal.
 
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