Definition talk:Poincaré Plane

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Is this a "hyperbolic plane" or a "Poincaré plane"? Presumably they are the same thing, but to call it one thing in the title and another thing in the body is bound to cause confusion. --prime mover (talk) 21:24, 6 November 2012 (UTC)

I've fixed your presubscripts: put open and close curly brackets before the underscore otherwise it thinks the previous thing is being subscripted. Spaces are in general ignored by the TeX compiler.
While I'm here I am unhappy about this:
${}_C L_R := \left\{{ {}_C L_R: C \in \R \land R \in \R_{>0}}\right\}$
How can ${}_C L_R$ contain itself, or am I missing the point of the notation? --prime mover (talk) 21:29, 6 November 2012 (UTC)
Although the book uses $\mathbb{H}$ it explicitly acknowledges that other scripts are used throughout the literature. It may be better suited to PW to change it now so it doesn't conflict with Definition:Quaternion. --Jshflynn (talk) 21:40, 6 November 2012 (UTC)

Definition in words

I wonder whether it is worth adding a few words on each concept to describe it, e.g. "half-plane above the real axis, the set of vertical half-lines", etc. whatever. --prime mover (talk) 22:07, 6 November 2012 (UTC)

I think so. Not sure what the "open ended semi-circles" should be referred to as though. --Jshflynn (talk) 22:13, 6 November 2012 (UTC)
Open ended semi-circles, innit. --prime mover (talk) 22:36, 6 November 2012 (UTC)