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There was a talk about this issue at the Midwest Science of Origins Conference on 31 March 2012 by Marco Peloso of the University of Minnesota. Peloso reviewed the evidence available for the condition of the Universe just after the Big Bang. He also mentioned that current observations are consistent with a "flat" geometry of the entire universe, but pointed out other lines of evidence, not mentioned in the blog post submitted here, consistent with a finite (although very, very large) size for the universe.

Finite size is consistent with current observations and theories, and an issue that the submitted article doesn't have a lot of space to address. Per a Wikipedia article,

http://en.wikipedia.org/wiki/Universe#Size.2C_age.2C_content...

consistent with what I heard in the lecture earlier this year, "The universe appears to have no net electric charge, and therefore gravity appears to be the dominant interaction on cosmological length scales. The universe also appears to have neither net momentum nor angular momentum. The absence of net charge and momentum would follow from accepted physical laws (Gauss's law and the non-divergence of the stress-energy-momentum pseudotensor, respectively), if the universe were finite." Wikipedia cites the Landau and Lifshitz physics textbook from the Soviet Union, Landau, Lev, Lifshitz, E.M. (1975). The Classical Theory of Fields (Course of Theoretical Physics, Vol. 2) (revised 4th English ed.). New York: Pergamon Press. pp. 358–397. ISBN 978-0-08-018176-9, for this statement.

Some multiverse theories such as those mentioned in another comment posted before this one can be overlaid on a simpler theory of a single finite "observable" (in principle) universe with the properties we know from human observation. Testing theories like those, or like the "level I multiverse" theory mentioned in the other comment, still needs more work.

The current Udacity course in physics

http://www.udacity.com/overview/Course/ph100/CourseRev/1

started off its first unit with the students reproducing the effort of Eratosthenes of Cyrene to measure the circumference of the earth more than 2,200 years ago. On reasonable assumptions known to the ancient Greeks, it was possible to get a surprisingly accurate estimate of the earth's circumference, with a major source of error being simply measuring distances between one city and another a few days' journey away.



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