# Difference between revisions of "Cross-surface"

Jump to navigation
Jump to search

m (Didn't know there was a template for this) |
m |
||

Line 13: | Line 13: | ||

==External links== | ==External links== | ||

{{LinkWikipedia|Real_projective_plane|name=Real projective plane}} | {{LinkWikipedia|Real_projective_plane|name=Real projective plane}} | ||

− | {{LinkGollyHelp|bounded.html}} | + | {{LinkGollyHelp|bounded.html|title=Bounded grids}} |

[[Category:Topologies]] | [[Category:Topologies]] |

## Revision as of 21:07, 29 October 2018

A **cross-surface** (or **real projective plane**) is a possible finite Life universe in the form of a real projective plane. The simplest way to do this is to use an m × n rectangle with the top edge twisted and joined to the bottom edge and the left edge twisted and joined to the right edge. It is similar to the Klein bottle except it has both pairs of sides twisted instead of just one.

## See also

## External links

- Real projective plane at Wikipedia

- Bounded grids at Golly's online help