On shrinking arcs in metric spaces

By a sin (1/x)-curve is meant a metric continuum that is a 1-1 continuous image of the disjoint union of an arc and a semi-open interval that has the image of the arc as continuum of convergence. It is shown that ifM is a compact metric space,A ⊂M an arc, whileM/A is an arc havingA/A as an end-point, thenM is an arc, a triod, some sin (1/x)-curve, or some sin (1/x)-curve with an arc attached at one point, or some sin (1/x)-curve with two arcs attached. The case of shrinking finitely many arcs is also considered in an attaching theorem. Prepared under a NASA Research Grant No. NsG-568 at Kent State University.