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arXiv · 1110.0091

A Banach algebraic Approach to the Borsuk-Ulam Theorem

Ali Taghavi
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Abstract

Using methods from the theory of commutative graded Banach algebras, we obtain a generalization of the two dimensional Borsuk-Ulam theorem as follows: Let $ϕ:S^{2} \rightarrow S^{2}$ be a homeomorphism of order n and $λ\neq 1$ be an nth root of the unity, then for every complex valued continuous function $f$ on $S^{2}$ the function $\sum_{i=0}^{n-1} λ^{i}f(ϕ^{i}(x))$ must be vanished at some point of $S^{2}$. We give a generalization in term of action of compact groups. We also discuss about some noncommutative versions of the Borsuk- Ulam theorem

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Ali Taghavi. 2013-10-15. A Banach algebraic Approach to the Borsuk-Ulam Theorem. https://doi.org/10.1155/2012%2F729745

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