A long-standing question in knot theory asks whether the set of algebraic knots is linearly independent in the knot concordance group; in other words, whether every nontrivial linear combination of algebraic knots fails to be slice. Since a slice knot is necessarily algebraically slice, a natural refinement of this question is whether an algebraically slice linear combination of algebraic knots must also be smoothly slice. In this talk, I will introduce an obstruction from Heegaard Floer d-invariants and discuss the techniques for computation.
Links:
[1] http://www.mpim-bonn.mpg.de/taxonomy/term/39
[2] http://www.mpim-bonn.mpg.de/node/3444
[3] http://www.mpim-bonn.mpg.de/node/12018