Can anyone helps me to understand what affine space is? Are we using in physics?
What does mean causal character?
An "affine space" is a point set in which we have a notion of "straight lines" and line segments. IF we choose a single point as the "0" and define vectors as the line segment from "0" to a given point, then we have a vector space. An "affine space" is like a vector space in which we have "forgotten" the 0 vector. "Cause" and "causal character" are physics concepts, not mathematics.
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