Cohomological framework for contextual quantum computations

Understand

We describe a cohomological framework for measurement based quantum computation, in which symmetry plays a central role.

• Therein, the essential information about the computational output is contained in topological invariants, namely elements of two cohomology groups.
• One of those invariants applies to the deterministic case, and the other to the general probabilistic case.
• The same invariants also witness quantumness in the form of contextuality.