Questions of Light and Space (Introduction)

by xeno6696 , Sonoran Desert, Tuesday, October 19, 2010, 12:05 (5149 days ago) @ Balance_Maintained

Look for FLRW model:-http://en.wikipedia.org/wiki/Shape_of_the_Universe-&quot;The curvature of space is a mathematical description of whether or not the Pythagorean theorem is valid for spatial coordinates. In the latter case, it provides an alternative formula for expressing local relationships between distances:- * If the curvature is zero, then &#206;&#169; = 1, and the Pythagorean theorem is correct.&#13;&#10; * If &#206;&#169; > 1, there is positive curvature, and&#13;&#10; * if &#206;&#169; < 1 there is negative curvature;-in either of these cases, the Pythagorean theorem is invalid (but discrepancies are only detectable in triangles whose sides&apos; lengths are of cosmological scale).-If you measure the circumferences of circles of steadily larger diameters and divide the former by the latter, all three geometries give the value &#207;&#128; for small enough diameters but the ratio departs from &#207;&#128; for larger diameters unless &#206;&#169; = 1:- * For &#206;&#169; > 1 (the sphere, see diagram) the ratio falls below &#207;&#128;: indeed, a great circle on a sphere has circumference only twice its diameter.&#13;&#10; * For &#206;&#169; < 1 the ratio rises above &#207;&#128;.-Astronomical measurements of both matter-energy density of the universe and spacetime intervals using supernova events constrain the spatial curvature to be very close to zero, although they do not constrain its sign. This means that although the local geometries of spacetime are generated by the theory of relativity based on spacetime intervals, we can approximate 3-space by the familiar Euclidean geometry.&quot;-WMAP suggests that the universe is flat--observation is within 2% of what we would expect a flat universe to look like. There are a few other geometries suggested that also map to this, but they are more complex, and therefore not favorable candidates.

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\"Why is it, Master, that ascetics fight with ascetics?\"

\"It is, brahmin, because of attachment to views, adherence to views, fixation on views, addiction to views, obsession with views, holding firmly to views that ascetics fight with ascetics.\"