Dear friends, Next Tuesday 30.4 at 11:00 in D1.13 we'll have a forum on some work I'm planning to submit for publication. It's a method of calculating using only circuit equivalences, with potential application to circuit optimization/transpilation. Title and abstract below. I'll show the basics and then open up the floor for feedback from you guys! Join us online at https://meet.jit.si/CQISeminarTalks Warmly, Will Title: Quantum circuits as a self-contained graphical language Abstract: Quantum circuit diagrams can be axiomatized as a standalone graphical language. Once imbued with a set of rewrite rules, circuits can be used to compute graphically. This provides a way to transform one circuit into another without converting to a more powerful graphical language like ZX-calculus, potentially circumventing the #P-hard 'circuit extraction problem' faced by ZX-based circuit optimizers. I present a preliminary list of rewrite rules for circuit diagrams. Depending on time and interest, I can show example calculations at the end.