The set of rational homotopy types with given cohomology algebra

Abstract

For a given commutative graded algebra $A^*$, we study the set ${\cal M}_{A^*} =$ $\{\mbox{rational homotopy type of }X \ $ $| \ H^*(X;Q)\cong A^*\}$. For example, we see that if $A^*$ is isomorphic to $H^*(S^3\vee S^5\vee S^{16};Q)$, then ${\cal M}_{A^*}$ corresponds bijectively to the orbit space $P^3(Q)/Q^*\coprod \{*\}$, where $P^3(Q)$ is the rational projective space of dimension 3 and the point $\{*\}$ indicates the formal space.