Deprecated: $wgMWOAuthSharedUserIDs=false is deprecated, set $wgMWOAuthSharedUserIDs=true, $wgMWOAuthSharedUserSource='local' instead [Called from MediaWiki\HookContainer\HookContainer::run in /var/www/html/w/includes/HookContainer/HookContainer.php at line 135] in /var/www/html/w/includes/Debug/MWDebug.php on line 372
Representing homotopy classes by maps with certain minimality root properties. II - MaRDI portal

Representing homotopy classes by maps with certain minimality root properties. II (Q2236454)

From MaRDI portal
scientific article
Language Label Description Also known as
English
Representing homotopy classes by maps with certain minimality root properties. II
scientific article

    Statements

    Representing homotopy classes by maps with certain minimality root properties. II (English)
    0 references
    25 October 2021
    0 references
    Let \(M\) be a surface in \(S^2\vee S^1\), \(A\in M\), \(B\in S^2\), \(P=S^1\cap S^2\) and \(D_A, D_B\) disks centered in \(A\) and \(B\), respectively. In this paper the authors show that for \(f:M\to S^2\vee S^1\) it is possible to find \(h:M\to S^2\vee S^1\) and \(k:S^2\to S^2\vee S^1\) such that \(h\) can be homotopically factored by \(h^{'}:M\to S^1\), that is, if \(\iota:S^1\to S^2\vee S^1\) is the inclusion then \(\iota\circ h^{' }=h\), \(h(A)=k(B)\) and \(f\simeq H(h,k)\) defined by \[ H(h,k)=\left\{ \begin{array}{c} h(z), z\in M- \mathring{D}_A\\ k(z), z\in S^2- \mathring{D}_B) \end{array}\right. .\] Then supposing that the decomposition \(\left[f\right]=\left[H(h,k)\right]\) is such that \(h\) and \(k \) are not null homotopic, the authors show that \begin{itemize} \item[1.] For \(y\in S^2-P\), there exists \(k_1\in [k]\) such that \(k_1^{-1}(y)\) is the root set for \(f\) since \(y \notin\mbox{image}(h)\). \item[2.] For \(y\in S^1\), there exists \(h_1\in [h]\) and \(k_2\in [k]\) such that \(h_1^{-1}(y)\cup k_2^{-1}(y)\) is the solution of the root problem for \(f\). \end{itemize} For Part I of this paper see [\textit{N. C. L. Penteado} and \textit{O. M. Neto}, Proc. R. Soc. Edinb., Sect. A, Math. 146, No. 5, 1005--1015 (2016; Zbl 1360.55001)].
    0 references
    roots of maps
    0 references
    homotopy theory
    0 references

    Identifiers

    0 references
    0 references
    0 references
    0 references
    0 references