For 3-dim Poincare Conjecture, the assumption is 'simply connected'. I am wondering whether simply connectedness assumption in 3-dim implies the same homotopy groups as the 3-sphere?

or If we switch the assumption of 'simply connected' to 'homotopy 3-sphere', would it be easier to proof Poincare Conjecuture.

Pleasedo double check your typing: the title of your question is the very first thing people see! – Mariano Suárez-Alvarez♦ Sep 23 '11 at 18:32