Subject: realization of algebra as rational cohomology of a manifold From: "pjz" Date: Fri, 31 Dec 2004 16:11:18 +0800 (CST) To: dmd1@lehigh.edu Dear fellow topologists: I have a question for your help. Given a graded Poincare duality algebra of finite dimension over rationals Q, A=\ sum A_i where A_0=Q and A_1=0 , Does there exists a manifold such that the rational cohomology ring of it isomorp hic as algebra to the given A. Anyone knows any reference about this problem? Maybe under some additional necess ary condition on A? Thank you for help. Best wishes Jianzhong Pan