• TBT's 2026 New Year's Party has started! Join us from now until January 11th in eight fun New Year's activities. Earn currency to spend on collectibles and raffle tickets. Get started in The Bulletin Board event thread. Happy New Year!

Ask salt

Consider a compact 3-dimensional manifold V without boundary. Is it possible that the fundamental group of V could be trivial, even though V is not homeomorphic to the 3-dimensional sphere?
 
Back
Top