Dick Lipton proposes the group isomorphism problem as a new polymath project.
The polymath blog
Recent Comments
Ten Recent Questions… on Two polymath (of a sort) propo… Anonymous on Rota’s Basis Conjecture:… Anonymous on Rota’s Basis Conjecture:… Anonymous on Polymath projects 2021 Richard Montgomery a… on Rota’s Basis Conjecture:… Anonymous on “Crowdmath” projec… Anonymous on Rota’s Basis Conjecture:… Anonymous on A sort of Polymath on a famous… Anonymous on A new polymath proposal (relat… Anonymous on Polymath projects 2021 Anonymous on Polymath proposal: bounded gap… Anonymous on (Research thread V) Determinst… Anonymous on A new polymath proposal (relat… Anonymous on Polymath8 – A Success… Anonymous on Polymath8 – A Success… 
Polymath Wiki – most recent changes- An error has occurred; the feed is probably down. Try again later.
The polymath blog 