- #1
pierce15
- 315
- 2
I am studying topology right now and am a bit confused about the idea of triangulation. The definition is: if a topological space X is homeomorphic to a polyhedron K (union of simplexes) then X is triangulable and K is a (not necessarily unique) triangulation.
Apparently ## K_0 \equiv {1} \cup {2} \cup {3} \cup {1,2} \cup {1,3} \cup {2,3} ## is a triangulation of ##S^1##, the unit circle in R2, and ##K \equiv K_0 \cup {1,2,3} ## is a triangulation of the unit disk in R2. The notation is that ##{i}## is a node, ##{i,j}## is a 1-simplex (edge), and ##{i,j,k}## is a 2-simplex (face).
I am having trouble seeing why these are homeomorphic, can anyone explain?
Apparently ## K_0 \equiv {1} \cup {2} \cup {3} \cup {1,2} \cup {1,3} \cup {2,3} ## is a triangulation of ##S^1##, the unit circle in R2, and ##K \equiv K_0 \cup {1,2,3} ## is a triangulation of the unit disk in R2. The notation is that ##{i}## is a node, ##{i,j}## is a 1-simplex (edge), and ##{i,j,k}## is a 2-simplex (face).
I am having trouble seeing why these are homeomorphic, can anyone explain?