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arXiv · 2306.14516

Co-operational bivariant theory

Shoji Yokura
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Abstract

For a covariant functor W. Fulton and R. MacPherson defined \emph{an operational bivariant theory} associated to this covariant functor. In this paper we will show that given a contravariant functor one can similarly construct a ``dual" version of an operational bivariant theory, which we call a \emph{co-operational} bivariant theory. If a given contravariant functor is the usual cohomology theory, then our co-operational bivariant group for the identity map consists of what are usually called ``cohomology operations". In this sense, our co-operational bivariant theory consists of \emph{``generalized"} cohomology operations.

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Shoji Yokura. 2023-06-26. Co-operational bivariant theory. https://doi.org/10.5802/mrr.20

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