Funtorofextension of-isometrimapsbetweenentralsubsetsofthe
unbounded Urysohn universal spae
Comment.Math.Univ.Carolin. 51,3 (2010)541{549.
Abstrat:TheaimofthepaperistoprovethatintheunboundedUrysohnuniversalspae
Uthereisafuntorofextensionof-isometrimaps(i.e.dilations)betweenentralsubsets
ofUto-isometrimapsatingonthewholespae. Speialpropertiesofthefuntorare
established. ItisalsoshownthatthemultipliativegroupRnf0gatsontinuouslyonU
by-isometries.
Keywords: Urysohn'suniversalspae, ultrahomogeneous spaes, funtor,extensions of
isometries
AMSSubjetClassiation:54C20,54E40,54E50
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