I haven’t read too closely, but it looks like the equivalence relation that you’re talking about in the post sets elements that are scalar multiples of each other in equivalence. This isn’t the point of my equivalence; the stuff I wrote is all in terms of vectors, not directions. My other top-level comment discusses this.
I haven’t read too closely, but it looks like the equivalence relation that you’re talking about in the post sets elements that are scalar multiples of each other in equivalence. This isn’t the point of my equivalence; the stuff I wrote is all in terms of vectors, not directions. My other top-level comment discusses this.