Title: On rationally slice knots

Abstract: A knot in the three-sphere is called slice if it bounds a smooth disk in the four-ball.

If one only requires the disk to be in a rational homology four-ball, then we say that the knot is rationally slice. We present a rationally slice knot which is not slice even after its connected self-sum. This is joint work with Jennifer Hom, Sungkyung Kang, and Matthew Stoffregen.