The closed subset theorem for inverse limits with upper semicontinuous bonding functions (Q2421409)

From MaRDI portal
scientific article
Language Label Description Also known as
English
The closed subset theorem for inverse limits with upper semicontinuous bonding functions
scientific article

    Statements

    The closed subset theorem for inverse limits with upper semicontinuous bonding functions (English)
    0 references
    0 references
    0 references
    0 references
    0 references
    0 references
    17 June 2019
    0 references
    Let \(X=\displaystyle{\lim_{\leftarrow}\{X_i,f_i\}}\) be an inverse limit of an inverse sequence \(\{X_i, f_i\}_{i=1}^{\infty}\) of compact metric spaces with continuous single-valued bonding functions. \textit{S. B. Nadler jun.} [Continuum theory. An introduction. New York: Marcel (1992; Zbl 0757.54009)] showed that any closed subset of the space \(X\) is the inverse limit of its projections. This is known as ``the closed subset theorem''. \textit{W. T. Ingram} [An introduction to inverse limits with set-valued functions. Berlin: Springer (2012; Zbl 1257.54033)] with an example showed that this theorem does not hold for inverse limits of inverse sequences of compact metric spaces with upper semicontinuous set-valued bonding functions. In the present paper, the authors give sufficient and necessary conditions on the bonding functions \(f_i: X_{i+1}\longrightarrow X_i\) for the inverse limit \(\displaystyle{\lim_{\leftarrow}\{X_i,f_i\}}\) to have the property that for any closed subset \(A\) of \(\displaystyle{\lim_{\leftarrow}\{X_i,f_i\}}\), \(A\) is the inverse limit of its projections.
    0 references
    closed subset theorem
    0 references
    inverse limit
    0 references
    set-valued function
    0 references
    0 references

    Identifiers

    0 references
    0 references
    0 references
    0 references
    0 references
    0 references