Realising sets of integers as mapping degree sets
Autor: | Neofytidis, Christoforos, Wang, Shicheng, Wang, Zhongzi |
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Rok vydání: | 2021 |
Předmět: | |
Zdroj: | Bull. Lond. Math. Soc. 55 (2023), 1700--1717 |
Druh dokumentu: | Working Paper |
Popis: | Given two closed oriented manifolds $M,N$ of the same dimension, we denote the set of degrees of maps from $M$ to $N$ by $D(M,N)$. The set $D(M,N)$ always contains zero. We show the following (non-)realisability results: (i) There exists an infinite subset $A$ of $\mathbb Z$ containing $0$ which cannot be realised as $D(M,N)$, for any closed oriented $n$-manifolds $M,N$. (ii) Every finite arithmetic progression of integers containing $0$ can be realised as $D(M,N)$, for some closed oriented $3$-manifolds $M,N$. (iii) Together with $0$, every finite geometric progression of positive integers starting from $1$ can be realised as $D(M,N)$, for some closed oriented manifolds $M,N$. Comment: 17 pages; v2: final version, to appear in Bulletin of the London Mathematical Society |
Databáze: | arXiv |
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