Recorded 29 November 2023. Jeongwan Haah of Microsoft Research presents "Global unitaries and local measurements" at IPAM's Topology, Quantum Error Correction and Quantum Gravity Workshop. Abstract: The space of all global unitaries that has lightcones displays an interesting topology, which leads to study of so-called quantum cellular automata. Connected components of this space correspond to local unitary circuits, and the existence of distinct connected components has been found and conjectured. I am going to discuss that a class of local measurement circuits, which includes those of Floquet codes, induce a strictly larger class of locality-preserving unitaries than that of local unitary circuits. Learn more online at: https://www.ipam.ucla.edu/programs/workshops/workshop-iv-topology-quantum-error-correction-and-quantum-gravity/