Skip to main content

Timeline for infinite dimensional polyhedra

Current License: CC BY-SA 3.0

13 events
when toggle format what by license comment
Feb 11, 2014 at 13:11 vote accept Ankur
Feb 7, 2014 at 14:46 answer added Gerald Edgar timeline score: 5
Feb 7, 2014 at 11:59 comment added Manfred Weis In the case of an countably infinite number of half-spaces, it should also be mentioned whether the set of normal directions is discrete or dense on the unit sphere.
Feb 7, 2014 at 10:07 comment added Manfred Weis @Ankur: I miss the restriction to a countable infinite number of intersecting half-spaces in the problem description; otherwise a sphere would also be an infinite convex polyhedron. Maybe in the title the restriction to convex polyhedra should also be mentioned.
Feb 7, 2014 at 9:01 answer added alpha timeline score: 3
Feb 7, 2014 at 3:08 answer added Tom LaGatta timeline score: 0
Feb 7, 2014 at 2:59 comment added Ankur In my case, I could have infinitely many half-spaces intersecting. Can something be said about this case? (I edited my question with this clarification)
Feb 7, 2014 at 2:58 history edited Ankur CC BY-SA 3.0
added 77 characters in body
Feb 6, 2014 at 20:35 comment added Wlodek Kuperberg @LevBorisov: The map you describe is in fact a projecion onto a finite-dimensional space in a direction parallel to each of the defining half-spaces. Therefore the original, infinite-dimensional polytope is the Cartesian product of a finite-dimensional one with an infinite-dimensional space. You should write your comment in the "answer" box.
Feb 6, 2014 at 19:42 review First posts
Feb 6, 2014 at 19:48
Feb 6, 2014 at 19:42 comment added Joseph O'Rourke You might look at Paolo d'Alessandro, "Generalizing polyhedra to infinite dimension," 2011. PDF download link.
Feb 6, 2014 at 19:41 comment added Lev Borisov If you have a finite number of half-spaces, then presumably you have a finite number of linear functions. Then you want to consider the span of these linear functions. This would give you a map from your infinite-dimensional space to a finite-dimensional space and all of the polytope business comes from the latter. So I think that you can separate the infinite-dimensional issues and the polyhedral issues.
Feb 6, 2014 at 19:24 history asked Ankur CC BY-SA 3.0