Rigidity and gluing for Morse and Novikov complexes

  • Octav Cornea

    University of Montréal, Canada
  • Andrew Ranicki

    University of Edinburgh, United Kingdom


We obtain rigidity and gluing results for the Morse complex of a real-valued Morse function as well as for the Novikov complex of a circle-valued Morse function. A rigidity result is also proved for the Floer complex of a hamiltonian defined on a closed symplectic manifold (M,ohgr) with c1|pgr2(M)=[ohgr]|pgr2(M)=0. The rigidity results for these complexes show that the complex of a fixed generic function/hamiltonian is a retract of the Morse (respectively Novikov or Floer) complex of any other sufficiently C0 close generic function/hamiltonian. The gluing result is a type of Mayer-Vietoris formula for the Morse complex. It is used to express algebraically the Novikov complex up to isomorphism in terms of the Morse complex of a fundamental domain. Morse cobordisms are used to compare various Morse-type complexes without the need of bifurcation theory.

Cite this article

Octav Cornea, Andrew Ranicki, Rigidity and gluing for Morse and Novikov complexes. J. Eur. Math. Soc. 5 (2003), no. 4, pp. 343–394

DOI 10.1007/S10097-003-0052-6