On geometric complexity theory: Multiplicity obstructions are stronger than occurrence obstructions

@inproceedings{Drfler2019OnGC,
title={On geometric complexity theory: Multiplicity obstructions are stronger than occurrence obstructions},
author={Julian D{\"o}rfler and Christian Ikenmeyer and G. Panova},
booktitle={ICALP},
year={2019}
}

Geometric Complexity Theory as initiated by Mulmuley and Sohoni in two papers (SIAM J Comput 2001, 2008) aims to separate algebraic complexity classes via representation theoretic multiplicities in coordinate rings of specific group varieties. The papers also conjecture that the vanishing behavior of these multiplicities would be sufficient to separate complexity classes (so-called occurrence obstructions). The existence of such strong occurrence obstructions has been recently disproven in 2016… Expand