  Concordance invariants of knots are derived from the instanton homology
groups with local coefficients, as introduced in earlier work of the authors.
These concordance invariants include a 1-parameter family of homomorphisms
$f_{r}$, from the knot concordance group to the reals. Prima facie, these
concordance invariants have the potential to provide independent bounds on the
genus and number of double points for immersed surfaces with boundary a given
knot.
