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Coincidence classes in nonorientable manifolds


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.



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Correspondence to Daniel Vendrúscolo.

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Vendrúscolo, D. Coincidence classes in nonorientable manifolds. Fixed Point Theory Appl 2006, 68513 (2006).

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  • Differential Geometry
  • Computational Biology
  • Product Formula
  • Root Classis
  • Coincidence Theory