|WikiProject Mathematics||(Rated Start-class, Mid-importance)|
The picture with the red plane dividing R^3 into white space and blue space looks a bit wrong. Shouldn't the blue fill the entire half of the space above the red plane instead of just the one octant?--18.104.22.168 23:33, 22 September 2007 (UTC)
- Would seem like that to me also. And I would note that in computer graphics, the words "half-space" are often used more generally, to describe any surface that partitions space into two distinct parts. (An infinitely long cylinder, or any closed shell, would all qualify as half-spaces.) 22.214.171.124 (talk) 07:40, 8 August 2008 (UTC)
Upper and lower half-spaces
Presuming that the terms "upper and lower half-space" are names for the regions on either side of the dividing plane, the definition given is only correct in the case when and . The most general definitions would be for an upper half space, and for a lower half space. These definitions don't say much more than the equations given at the top of the page, and could perhaps be incorporated into that section.