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The best description of Newton's conundrum, and its modern resolution, may be found on pages 295-297 in the 1997 Basic Books ed. of Guth's book titled "The Inflationary Universe", which uses simple algebra and one diagram to illustrate that resolution. Newton's thinking (accurately described in John Hunter's answer) contained one flaw: He failed ...


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There are many possible matter models in General Relativity. In Cosmology, a family of simple models are obtained by using perfect fluids and the assumption that $p = w \rho$ for some $w$ that in simple models is taken to be a constant. In this framework, notice your model consists of taking $w = 0$. This is actually a fairly common matter model, which we ...


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Here is the link describing the 5 dimensional space-time approach, developed by Tim Andersen, Ph.D. https://medium.com/the-infinite-universe/general-relativity-may-create-quantum-physics-949fffb1c7c


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Physics does not in general answer the question of why something fundamental exists, nor does it seek to assign a purpose to anything. Rather, it tries to build a model to understand how different fundamental things interact with each other. Energy is one example. It is not a theoretical artifact, but rather a physical substance intrinsic to the Universe. ...


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Why is there any Energy at all? The simple answer that is preferred by modern physicists is that there is energy because the laws of physics are the same today as they were yesterday. It is the fact that the laws of physics do not change over time that leads to energy. Of course, that begs the question "why are the laws of physics the same over time&...


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I understand it like that: If there was a finite number of stars evenly distributed in, let's say a spherical region of the universe. Then if we consider the stars on the "surface" of this sphere, there are no gravitational forces pulling them away from the center of the sphere. However, since there are many stars closer to the center of the sphere,...


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Newton thought that if the number of stars was finite they would all fall towards the centre of mass and all end up together there. As that hasn't happened he argued that there could be an infinite number of stars.


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'What is meant by "dimension"?' As the question is asked above, I think we are talking about the nature of reality. In our physical world, 3 dimensions are required to differentiate any and all points that any physical object can occupy. If our universe was static that would be sufficient but the universe and its contents are not static so a 4th ...


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