In rational homotopy theory, the Halperin conjecture concerns the Serre spectral sequence of certain fibrations. It is named after the Canadian mathematician Stephen Halperin.

Statement

Suppose that F → E → B {\displaystyle F\to E\to B} is a fibration of simply connected spaces such that F {\displaystyle F} is rationally elliptic and χ ( F ) ≠ 0 {\displaystyle \chi (F)\neq 0} (i.e., F {\displaystyle F} has non-zero Euler characteristic), then the Serre spectral sequence associated to the fibration collapses at the E 2 {\displaystyle E_{2}} page.

Status

As of 2019, Halperin's conjecture is still open. Gregory Lupton has reformulated the conjecture in terms of formality relations.

Notes

Further reading