Speaker
Description
Quantum resources have entered the many body stage over the last two decades. Apart from the prototypical case of entanglement, relatively little is known about how such resources relate to physical phenomena, a question that is of pivotal importance for the understanding of quantum simulators and computers as many-body systems.
In this talk, I will show how magic - a type of resource that is fundamental in determining quantum advantage - is directly related to many-body phenomena. First, I will introduce basic theoretical concepts, and explain why magic is the ultimate resource bottleneck for quantum computing applications that utilize error corrections. Then, after a brief review of what is known for conventional statistical mechanics models, I will present a throughout investigation of magic in a one-dimensional U(1) lattice gauge theory. The results indicate that magic is always extensive with volume, and has no direct relation to the presence of critical points. However, its derivatives typically display discontinuities across the latter: this indicates that magic is strongly sensitive to criticality, but in a manner that is very different from entanglement (that, typically, is maximal at critical point). Our results indicate that error-corrected simulations of lattice gauge theories close to the continuum limit have similar computational cost that those at finite correlation length, and provides rigorous lower bounds for quantum resources of such quantum computations.
