Title of article :
Making equivariant maps fixed point free
Author/Authors :
Ferrario، نويسنده , , Davide L. Ferrario، نويسنده ,
Issue Information :
دوماهنامه با شماره پیاپی سال 2001
Abstract :
One of the most crucial questions in (Nielsen) equivariant fixed point theory is the following. Let G be a compact Lie group, and X a G-space. Given an equivariant map f :X→X such that for each subgroup H⊂G, fH :XH→XH can be deformed to be fixed point free by a compactly fixed homotopy, is it true that f can be deformed by a compactly fixed G-homotopy to a fixed point free map? Furthermore, if the Nielsen numbers N(fH) vanish, is it true that f can be equivariantly deformed to be fixed point free (converse of the Lefschetz property for nG)? Fadell and Wong [Pacific J. Math. 132 (1988) 277–281] gave positive answers to these questions, under the hypothesis that dim(XHs)+2⩽dim(XH) (Codimension Hypothesis). In this paper we prove that if f is isovariant, and the group G is 2-split, then the converse of the Lefschetz Property for nG holds for G-manifolds of dimension ≠2. We also give a counter-example that illustrates why in general the Codimension Hypothesis cannot be removed from the main result of Fadell and Wong, unless assuming further hypotheses.
Keywords :
Equivariant fixed point theory , Nielsen number , Wecken property
Journal title :
Topology and its Applications
Journal title :
Topology and its Applications