Higher convexity of tropical objects
Mounir Nisse and Frank Sottile
Gromov generalized the notion of convexity for open subsets of R with hypesurface boundary, defining k-convexity, or higher convexity and Henriques applied the same notion to complements of amoebas. He conjectured that the complement of an amoeba of a variety of codimension k+1 is k-convex. I will discuss work with Mounir Nisse in which we study the higher convexity of complements of coamoebas and of tropical varieties, proving Henriques' conjecture for coamoebas and establishing a form of Henriques' conjecture for tropical varieties in some cases.
Below, we show the amoeba and coamoeba of a line in (C*)3.


Amoeba of the line t --> (t-1, t-ζ, t2),
where ζ is a primitive third root of 1.


CoAmoeba of the same line.
Last modified: Thu Oct 22 19:01:30 CDT 2015