Circle-valued Morse theory for frame spun knots and surface-links

Autor: Hisaaki Endo, Andrei Pajitnov
Přispěvatelé: Tokyo Institute of Technology [Tokyo] (TITECH), Laboratoire de Mathématiques Jean Leray (LMJL), Centre National de la Recherche Scientifique (CNRS)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: The Michigan Mathematical Journal
The Michigan Mathematical Journal, Michigan Mathematical Journal, 2017, 66 (4), pp.813-830. ⟨10.1307/mmj/1508810816⟩
Michigan Math. J. 66, iss. 4 (2017), 813-830
ISSN: 0026-2285
DOI: 10.1307/mmj/1508810816⟩
Popis: Let N be a closed oriented k-dimensional submanifold of the (k+2)-dimensional sphere; denote its complement by C(N). Denote by x the 1-dimensional cohomology class in C(N), dual to N. The Morse-Novikov number of C(N) is by definition the minimal possible number of critical points of a regular Morse map f from C(N) to a circle, such that f belongs to x. In the first part of this paper we study the case when N is the twist frame spun knot associated to an m-knot K. We obtain a formula which relates the Morse-Novikov numbers of N and K and generalizes the classical results of D. Roseman and E.C. Zeeman about fibrations of spun knots. In the second part we apply the obtained results to the computation of Morse-Novikov numbers of surface-links in 4-sphere.
13 pages
Databáze: OpenAIRE