If (X,d) is a metric space, then we say that a closed subset A of X is a z-set if for each number k>0 there is a continuous map fk from X into X-A such that d(x,fk(x))<k.
I am wondering if a z-set in the Hilbert cube is a deformation retract of it?
If (X,d) is a metric space, then we say that a closed subset A of X is a z-set if for each number k>0 there is a continuous map fk from X into X-A such that d(x,fk(x))<k.
I am wondering if a z-set in the Hilbert cube is a deformation retract of it?