Quantum Mechanics
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Classical dynamics generated by longrange interactions for lattice fermions and quantum spins
(2021)We study the macroscopic dynamical properties of fermion and quantumspin systems with longrange, or meanfield, interactions. The results obtained are far beyond previous ones and require the development of a mathematical ... 
Macroscopic Dynamics of the StrongCoupling BCSHubbard Model,
(2020)The aim of the current paper is to illustrate, in a simple example, our recent, very general, rigorous results on the dynamical properties of fermions and quantumspin systems with longrange, or meanfield, interactions, ... 
Lieb–Robinson Bounds for Multi–Commutators and Applications to Response Theory
(2017)We generalize to multicommutators the usual Lieb–Robinson bounds for commutators. In the spirit of constructive QFT, this is done so as to allow the use of combinatorics of minimally connected graphs (tree expansions) in ... 
Quantum Dynamics Generated by LongRange Interactions for Lattice Fermion and Quantum Spins
(2021)We study the macroscopic dynamics of fermion and quantumspin systems with longrange, or meanfield, interactions, which turns out to be equivalent to an intricate combination of classical and shortrange quantum dynamics. ... 
Equilibrium and Transport Properties of Quantum ManyBody Systems
(20191030)This thesis is a study of equilibrium and dynamical properties of macroscopic quantum manybody problems. An important part of the manuscript concerns the study of heat and charge transport properties of fermions on the ... 
Noncooperative Equilibria of Fermi Systems With Long Range Interactions
(201307)We define a Banach space $\mathcal{M}_{1}$ of models for fermions or quantum spins in the lattice with long range interactions and explicit the structure of (generalized) equilibrium states for any $\mathfrak{m}\in ... 
Isotropic BipolaronFermionExchange Theory and Unconventional Pairing in Cuprate Superconductors
(20181210)The discovery of hightemperature superconductors in 1986 represented a major experimental breakthrough (Nobel Prize 1987), but their theoretical explanation is still a subject of much debate. These materials have many ... 
Accuracy of Classical Conductivity Theory at Atomic Scales for Free Fermions in Disordered Media
(20190122)The growing need for smaller electronic components has recently sparked the interest in the breakdown of the classical conductivity theory near the atomic scale, at which quantum effects should dominate. In 2012, experimental ... 
Decay of Complextime Determinantal and Pfaffian\ Correlation Functionals in Lattices
(20180124)We supplement the determinantal and Pfaffian bounds of Sims and Warzel (Commun Math Phys 347:903931, 2016) for manybody localization of quasifree fermions, by considering the high dimensional case and complextime ... 
The Discretenessdriven Relaxation of Collisionless Gravitating Systems: Entropy Evolution in External Potentials, Ndependence, and the Role of Chaos
(20190110)We investigate the old problem of the fast relaxation of collisionless Nbody systems that are collapsing or perturbed, emphasizing the importance of (noncollisional) discreteness effects. We integrate orbit ensembles in ... 
Measurevalued weak solutions to some kinetic equations with singular kernels for quantum particles
(20181219)In this thesis, we present a mathematical study of three problems arising in the kinetic theory of quantum gases. In the first part, we consider a Boltzmann equation that is used to describe the time evolution of the ... 
On a Boltzmann equation for Compton scattering, from non relativistic electrons at low density.
(20180815)A Boltzmann equation, used to describe the Compton scattering in the nonrelativistic limit is considered. A truncation of the very singular redistribution function is introduced and justified. The existence of weak solutions ... 
On a system of equations for the normal fluid  condensate interaction in a Bose gas
(20180327)The existence of global solutions for a system of differential equations is proved, and some of their properties are described. The system involves a kinetic equation for quantum particles. It is a simplified version of ... 
Existence of “$d$wave” Pairs and Density Waves in a Class of Microscopic Models for High Transition Temperature Superconductors
(20180321)Hightemperature superconductors have different properties than conventional superconductors, one of these important properties is nonisotropic symmetry of the order parameter. In this work we present a model that shows ... 
Universal bounds for large determinants from noncommutative Hölder inequalities in fermionic constructive quantum field theory
(20170802)Efficiently bounding large determinants is an essential step in nonrelativistic fermionic constructive quantum field theory to prove the absolute convergence of the perturbation expansion of correlation functions in terms ... 
Isotropic BipolaronFermionExchange Theory and Unconventional Pairing in Cuprate Superconductors
(20170503)The discovery of hightemperature superconductors in 1986 represented a major experimental breakthrough (Nobel Prize 1987), but their theoretical explanation is still a subject of much debate. These materials have many ... 
Geometric inequalities from phase space translations
(20160722)We establish a quantum version of the classical isoperimetric inequality relating the Fisher information and the entropy power of a quantum state. The key tool is a Fisher information inequality for a state which results ... 
Kinetic energy estimates for the accuracy of the timedependent HartreeFock approximation with Coulomb interaction
(20160101)We study the time evolution of a system of $N$ spinless fermions in $\mathbb{R}^3$ which interact through a pair potential, e.g., the Coulomb potential. We compare the dynamics given by the solution to Schrödinger's equation ... 
Diagonalizing quadratic bosonic operators by nonautonomous flow equations volker bach
(20160101)We study a nonautonomous, nonlinear evolution equation on the space of operators on a complex Hilbert space. We specify assumptions that ensure the global existence of its solutions and allow us to derive its asymptotics ... 
Microscopic conductivity of lattice fermions at equilibrium. I. Noninteracting particles
(20151231)We consider free lattice fermions subjected to a static bounded potential and a timeand spacedependent electric field. For any bounded convex region R âŠ‚ â„ (d (d â‰¥ 1) of space, electric fields Îµ within R drive currents. ...