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Rotation by reflection

This diagram illustrates how the rotation x -> x'' in can be constructed by two successive reflections at
planes (blue and red)
which enclose half the angle of the desired rotation angle. Only the component xs of the vector x in the plane of the two
vectors n and m is affected. It is therefore sufficient to only be concerned with this plane perpendicular to the axis of
rotation. Change the vectors interactively by dragging the red points.

This also illustrates rotation behavior of a spinor!

Compare the simple plane case.

[ GA with Cinderella ]

Soli Deo Gloria. Created with Cinderella
by Eckhard Hitzer (Fukui).