Talk:Borel Conjecture for the 2-torus (Ex)
From Manifold Atlas
Suggestion:
1. Note that the dimensions must be equal.
2. Use the homotopy classification of surfaces, so both surfaces must be .
3. Use the square model for the torus with edges identified, lying in a grid. Assume WLOG that the map preserves orientation (if not, then flip it). Homotope the map to the identity map.