Let \(M\) be a compact orientable manifold with boundary. Use differential forms to show that there is no smooth retraction \(r:M\to \partial M\).
Question
Math 6510 • Differentiable Manifolds
Spring 2008 • Question 3
Question
Spring 2008 • Question 3
Let \(M\) be a compact orientable manifold with boundary. Use differential forms to show that there is no smooth retraction \(r:M\to \partial M\).