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Top Document: [sci.astro] Cosmology (Astronomy Frequently Asked Questions) (9/9) Previous Document: I.02. Why do astronomers favor the Big Bang model of the Universe? Next Document: I.04. What do people mean by an "open," "flat," or "closed" Universe? See reader questions & answers on this topic! - Help others by sharing your knowledge Often when people are told that galaxies are receding from us, they assume that means we are at the center of the Universe. However, remember that the Universe is homogeneous and isotropic. No matter where one is, it looks the same in all directions. Thus, all galaxies see all other galaxies receding from them. Hubble's relationship is compatible with a Copernican view of the Universe: Our position is not a special one. So where is the center? *There isn't one*. Although apparently nonsensical, consider the same question about the *surface* of a sphere (note the *surface*). Where's the center of a sphere's surface? Of course, there isn't one. One cannot point to any point on a sphere's surface and say that, here is the center. Similarly, because the Universe is homogeneous and isotropic, all we can say is that, in the past, galaxies were closer together. We cannot say that galaxies started expanding from any particular point. User Contributions:Top Document: [sci.astro] Cosmology (Astronomy Frequently Asked Questions) (9/9) Previous Document: I.02. Why do astronomers favor the Big Bang model of the Universe? Next Document: I.04. What do people mean by an "open," "flat," or "closed" Universe? Part0 - Part1 - Part2 - Part3 - Part4 - Part5 - Part6 - Part7 - Part8 - Single Page [ Usenet FAQs | Web FAQs | Documents | RFC Index ] Send corrections/additions to the FAQ Maintainer: jlazio@patriot.net
Last Update March 27 2014 @ 02:11 PM
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