Talk:Borel Conjecture for the 2-torus (Ex)

Suggestion:

1. Note that the dimensions must be equal.

2. Use the homotopy classification of surfaces, so both surfaces must be $T^2$$<wikitex>; Suggestion: 1. Note that the dimensions must be equal. 2. Use the homotopy classification of surfaces, so both surfaces must be $T^2$. 3. Use the square model for the torus with edges identified. Assume WLOG that the map preserves orientation. We'll homotope the map to the identity map. Homotope the boundaries to each other one at a time; this turns the interior into an open square. Then homotope the interior to itself. </wikitex>T^2$.

3. Use the square model for the torus with edges identified. Assume WLOG that the map preserves orientation. We'll homotope the map to the identity map. Homotope the boundaries to each other one at a time; this turns the interior into an open square. Then homotope the interior to itself.