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The relative coincidence Nielsen number

Jerzy Jezierski (1996)

Fundamenta Mathematicae

We define a relative coincidence Nielsen number N r e l ( f , g ) for pairs of maps between manifolds, prove a Wecken type theorem for this invariant and give some formulae expressing N r e l ( f , g ) by the ordinary Nielsen numbers.

The semi-index product formula

Jerzy Jezierski (1992)

Fundamenta Mathematicae

We consider fibre bundle maps (...) where all spaces involved are smooth closed manifolds (with no orientability assumption). We find a necessary and sufficient condition for the formula    |ind|(f,g:A) = |ind| (f̅,g̅: p(A)) |ind| ( f b , g b : p - 1 ( b ) A ) to hold, where A stands for a Nielsen class of (f,g), b ∈ p(A) and |ind| denotes the coincidence semi-index from [DJ]. This formula enables us to derive a relation between the Nielsen numbers N(f,g), N(f̅,g̅) and N ( f b , g b ) .

The universal functorial Lefschetz invariant

Wolfgang Lück (1999)

Fundamenta Mathematicae

We introduce the universal functorial Lefschetz invariant for endomorphisms of finite CW-complexes in terms of Grothendieck groups of endomorphisms of finitely generated free modules. It encompasses invariants like Lefschetz number, its generalization to the Lefschetz invariant, Nielsen number and L 2 -torsion of mapping tori. We examine its behaviour under fibrations.

The Wecken property of the projective plane

Boju Jiang (1999)

Banach Center Publications

A proof is given of the fact that the real projective plane P 2 has the Wecken property, i.e. for every selfmap f : P 2 P 2 , the minimum number of fixed points among all selfmaps homotopic to f is equal to the Nielsen number N(f) of f.

Theorem on signatures

Władysław Kulpa, Andrzej Szymański (2007)

Acta Universitatis Carolinae. Mathematica et Physica

Topological complexity of motion planning and Massey products

Mark Grant (2009)

Banach Center Publications

We employ Massey products to find sharper lower bounds for the Schwarz genus of a fibration than those previously known. In particular we give examples of non-formal spaces X for which the topological complexity TC(X) (defined to be the genus of the free path fibration on X) is greater than the zero-divisors cup-length plus one.

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