Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The center of the infinite universe

  1. Aug 20, 2010 #1
    I just recently discovered that the sun may be the center of the galaxy and what not, but if the universe is infinite, there is no center. furthermore, dealing with the outer limits of the universe, what is the shape of the universe? it can be a sphere? wouldnt this mean that the terms circle, square, etc., being used to describe the shape of the infinite universe are erroneous and rather outdated?
  2. jcsd
  3. Aug 21, 2010 #2


    User Avatar
    Science Advisor

    No, our sun is pretty far out to the side. This link has an image that gets you an idea of where our sun lies:
    http://www.star.le.ac.uk/educ/ourgalaxy.html [Broken]

    (note: this is, of course, not an actual image of our galaxy, because we're in it! It's another galaxy that has similar structure to our own.)

    We don't know what the overall shape of our universe is. There is a horizon that limits our vision, due to how our universe has expanded with time. Because of this horizon, the most we can say is that our universe is significantly larger than the part of it we can see. But we don't know what the overall shape is.
    Last edited by a moderator: May 4, 2017
  4. Aug 22, 2010 #3


    User Avatar
    Science Advisor
    Gold Member

    We can safely say the universe is at least 13.7 bly in all directions from earth. We cannot deduce if it is larger [due to the horizon thing chalnoth noted]. It may curve back upon itself, or be utterly flat out to infinity. There is no known experiment [or observation] known to date capable of resolving that issue. We do, however, know the observable universe is temporally finite.
  5. Aug 22, 2010 #4
    To determine center we need peripheries. An infinite universe by definition has no peripheries. Therefore it can have no center. Actually, it's even questionable that such a universe could even exist at all.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook