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
A metric characterization of the irrationals via a group operation - MaRDI portal

A metric characterization of the irrationals via a group operation (Q1074168)

From MaRDI portal





scientific article; zbMATH DE number 3947182
Language Label Description Also known as
English
A metric characterization of the irrationals via a group operation
scientific article; zbMATH DE number 3947182

    Statements

    A metric characterization of the irrationals via a group operation (English)
    0 references
    0 references
    1985
    0 references
    A metric d for a topological space S is called a spyc metric if for each point x in S and each nonnegative real number r there exists a unique point y in S such that \(d(x,y)=r\). A space S is called a spyc space if it is separable and has a topology preserving spyc metric. Such a space is actually constructed in the plane. (1) There exist more than continuum- many nonhomeomorphic examples of spyc spaces. (2) Each complete spyc space is homeomorphic to the space of irrationals. An interesting matrix, called spyc, is defined. This matrix clarifies the subject.
    0 references
    zero-dimensional spaces
    0 references
    spyc metric
    0 references
    spyc space
    0 references
    space of irrationals
    0 references

    Identifiers