6 papers
Invariant measures of randomized quantum trajectories
Tristan Benoist, Sascha Lill, Cornelia Vogel
Quantum trajectories are Markov chains modeling quantum systems subjected to repeated indirect measurements. Their stationary regime depends on what observables are measured on the…
The Ground State Energy of a Mean-Field Fermi Gas in Two Dimensions
Gregorio Casadei, Sascha Lill
We rigorously establish a formula for the correlation energy of a two-dimensional Fermi gas in the mean-field regime for potentials whose Fourier transform satisfies $\ha…
Renormalization of generalized spin-boson models with critical ultraviolet divergences
Benjamin Alvarez, Sascha Lill, Davide Lonigro +1
We provide a rigorous construction of generalized spin--boson models with commuting transition matrices and form factors exhibiting critical ultraviolet (UV) divergences. That is,…
Implementing Bogoliubov Transformations Beyond the Shale-Stinespring Condition
Sascha Lill
We provide two extensions of a dense subspace of Fock space, such that Bogoliubov transformations become implementable on them, even though they violate the Shale-Stinespring condi…
Extended State Space for describing renormalized Fock spaces in QFT
Sascha Lill
We revisit the non-perturbative renormalization of a class of simple polaron models with resting fermions. The considered dispersion relations and form factors are allowed to be hi…
Self-adjointness and domain of generalized spin-boson models with mild ultraviolet divergences
Sascha Lill, Davide Lonigro
We provide a rigorous construction of a large class of generalized spin-boson models with ultraviolet-divergent form factors. This class comprises various models of many possibly n…