Glasnik Matematicki, Vol. 37, No.2 (2002), 375-382.
THE PROPERTY RNT ON DENDROIDS
Veronica Martinez-de-la-Vega
Instituto de Matematicas, UNAM,
Circuito Exterior, Cd. Universitaria,
Mexico, 04510, D.F., Mexico
e-mail: vmvm@matem.unam.mx
Abstract. A continuum is said to be
retractable onto near trees (abbreviating RNT)
provided that for each
ε > 0
there exists
δ > 0
such that if T is a
tree in X and H(T,X) <
δ,
then there exists an
ε-retraction r of X onto T.
In this paper it is
proved that an arcwise connected continuum with the property RNT
is a dendroid. We focus our study on dendroids. Dendrites are
characterized as: (a) smooth dendroids with property RNT,
(b) dendroids with the property RNT hereditarily. Finally, an
example of a nonlocally connected dendroid with property RNT is
shown.
2000 Mathematics Subject Classification.
54F15, 54F50, 54F65, 54C15.
Key words and phrases. Continuum, dendrite, dendroid,
retraction, tree.
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