In this talk I will outline a novel approach to quantum mereology based on minimal information scrambling. Generalized quantum subsystems are defined by pairs of von Neumann algebras and their commutant and their scrambling in terms of a novel Algebraic Out of Time Order Correlation (A-OTOC) function. The short time expansion of the A-OTOC allows one to define a notion of Gaussian Scrambling rate. The latter has a simple geometrical interpretation, and its local minima provide an operational criterion for the selection of emergent subsystems. Examples of factors and maximal abelian algebras will be discussed and shown that in these key cases the formalism leads to physically meaningful connections to operator entanglement and to coherence generating power respectively.
P. Zanardi, E. Dallas, S. Lloyd, Operational Quantum Mereology and Minimal Scrambling, arXiv:2212.14340
P. Zanardi, Quantum scrambling of observable algebras, Quantum 6, 666 (2022),