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benorin

Homework Helper

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## Main Question or Discussion Point

I've been trying to wrap my head around the geometry of the expansion of space, from Science Channel shows I vaguely understand the "every point in space is moving away from every other point in space" and iirc this was uniformly so. Is that correct? If not ignore the rest of this post I suppose because I assume it true for the following: suppose that at a given point in time three galaxies taken as points at their centers form a ##1 : 1 : \sqrt{2}## right triangle. What sort of triangle will these galaxies form later? Let the distance between any two points in space be increased by a length h due to the expansion of space at that time we again measure the triangle, then since each side of the triangle is just the distance between two points itself we will have a ## 1+h : 1+h : \sqrt{2}+h ## triangle, some simple algebra reveals that this is an isosceles triangle which is not a right triangle, so the expansion of space does not preserve right triangles? Not knowing even if I have a correct underlying definition, I will stop here and wait for confirmation. Please correct me if need be and feel free to illuminate any thing you think is in the vein of this post.