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Opalg · #3 July 28th, 2009, 12:11 PM

Quote:

Originally Posted by Sooz

Hi,
I'm told that symmetries in hyperbolic space is $o^+ (1,2)$ - I'm not sure what that is!

I think it should probably be a capital O (for orthogonal). Then the group of symmetries of hyperbolic space, $O^+ (1,2)$ , ought to mean the group of 3×3 matrices with positive determinant (that's what the + is for) that preserve the quadratic form $x_1^2-x_2^2-x_3^2$ (which has 1 positive and 2 negative terms).