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arXiv · 2512.19461

Secondary cohomology operations and sectional category

Mark Grant
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Abstract

We show how secondary cohomology operations in the total space of the fibred join can be used to give lower bounds for the sectional category of a fibration. This suggests a refinement of the module weight of Iwase--Kono, which we call the secondary module weight. Examples are given for which the secondary module weight at the prime $2$ detects sectional category while the module weight does not.

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Mark Grant. 2025-12-22. Secondary cohomology operations and sectional category. https://arxiv.org/abs/2512.19461

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