Contextuality of transformations

I will introduce a notion of contextuality for transformations in sequential contexts. It is distinct from the notions of contextuality due to Bell-Kochen-Specker and Spekkens. There is considerable evidence that contextuality of these latter forms lies at the root of certain forms of quantum advantage over classical systems for performing a variety of informatic tasks. I will present a basic example where sequential transformation contextuality can be seen to lead to similar advantage in single qubit protocols, where contextuality of the other forms could not be present. Much of this talk will be based on recent joint work with Elham Kashefi, which can be found at https://arxiv.org/abs/1801.08150.