Romain Vasseur: Measurement-induced entanglement in gapless matter

Local measurements can radically reshape patterns of many-body entanglement, especially in long-range entangled quantum-critical states. Yet, analytical results addressing the effects of measurements on many-body states remain scarce, and measurements are often approximated as forcing specific measurement outcomes. In this talk, I will discuss the measurement-induced entanglement (MIE) in Tomonaga-Luttinger liquids, a broad family of 1+1d quantum critical states described at low energies by compact free boson conformal field theories (CFT). Measuring the local charge operator, I will show that the MIE is entirely universal, conformally invariant, and can be computed exactly using a replica trick. I will also discuss recent ongoing work on the full distribution of MIE, and comment on the general description of measurements in quantum field theories.