## Speaker:

Prof. M. Culler

## Institution:

UIC

## Time:

Wednesday, November 12, 2003 - 2:00pm

## Location:

MSTB 254

We consider a knot in a homotopy lens space which has exactly two essential surfaces, excluding fibers and semi-fibers.(The figure eight knot is an example.) For such knots there are interesting inequalities that bound the denominator of the boundary slope of one surface in terms of the topological type of the other surface and the intersection number of the two slopes. This is joint

work with Peter Shalen.