Open Access

Coincidence classes in nonorientable manifolds

Fixed Point Theory and Applications20062006:68513

DOI: 10.1155/FPTA/2006/68513

Received: 15 September 2004

Accepted: 21 July 2005

Published: 2 March 2006


We study Nielsen coincidence theory for maps between manifolds of same dimension regardless of orientation. We use the definition of semi-index of a class, review the definition of defective classes, and study the occurrence of defective root classes. We prove a semi-index product formula for lifting maps and give conditions for the defective coincidence classes to be the only essential classes.


Authors’ Affiliations

Departamento de Matemútica, Universidade Federal de Sáo Carlos


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© Daniel Vendrúscolo. 2006

This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.