 Rational homotopy theory

Study homotopy after killing torsion, especially for simply connected spaces of finite type. The rational Whitehead theorem detects rational homotopy equivalences by rational homology, while Sullivan minimal models encode rational homotopy generators and cohomological relations.

Rational homotopy theory is a branch of algebraic topology that studies spaces using rational coefficients. It focuses on understanding the homotopy type of topological spaces by considering their behavior when coefficients are taken in the field of rational numbers \(\mathbb{Q}\).