Zobrazeno 1 - 10
of 95
pro vyhledávání: '"Lampart, Jonas"'
Autor:
Lampart, Jonas, Triay, Arnaud
We analyze the many-body Hamiltonian describing a mobile impurity immersed in a Bose-Einstein condensate (BEC). Using exact unitary transformations and rigorous error estimates, we show the validity of the Bogoliubov-Fr\"ohlich Hamiltonian for the Bo
Externí odkaz:
http://arxiv.org/abs/2411.11655
We prove that the bulk magnetization is equal to the edge current in the thermodynamic limit for a large class of models of lattice fermions with finite-range interactions satisfying local indistinguishability of the Gibbs state, a condition known to
Externí odkaz:
http://arxiv.org/abs/2403.17566
Autor:
Lampart, Jonas, Triay, Arnaud
We study a dilute system of $N$ interacting bosons coupled to an impurity particle via a pair potential in the Gross--Pitaevskii regime. We derive an expansion of the ground state energy up to order one in the boson number, and show that the differen
Externí odkaz:
http://arxiv.org/abs/2401.14911
Autor:
Hinrichs, Benjamin, Lampart, Jonas
In the Bogoliubov-Fr\"ohlich model, we prove that an impurity immersed in a Bose-Einstein condensate forms a stable quasi-particle when the total momentum is less than its mass times the speed of sound. The system thus exhibits superfluid behavior, a
Externí odkaz:
http://arxiv.org/abs/2311.05361
We consider the time evolution of the renormalized Nelson model, which describes $N$ bosons linearly coupled to a quantized scalar field, in the mean-field limit of many particles $N\gg 1$ with coupling constant proportional to $N^{-1/2}$. First, we
Externí odkaz:
http://arxiv.org/abs/2305.06722
For the Fr\"ohlich model of the large polaron, we prove that the ground state energy as a function of the total momentum has a unique global minimum at momentum zero. This implies the non-existence of a ground state of the Fr\"ohlich Hamiltonian and
Externí odkaz:
http://arxiv.org/abs/2206.14708
Autor:
Lampart, Jonas
Publikováno v:
Annales Henri Poincare 24 (2023)
We treat the ultraviolet problem for polaron-type models in nonrelativistic quantum field theory. Assuming that the dispersion relations of particles and the field have the same growth at infinity, we cover all subcritical (superrenormalisable) inter
Externí odkaz:
http://arxiv.org/abs/2203.07253
We study the Dirac equation coupled to scalar and vector Klein-Gordon fields in the limit of strong coupling and large masses of the fields. We prove convergence of the solutions to those of a cubic non-linear Dirac equation, given that the initial s
Externí odkaz:
http://arxiv.org/abs/2110.09087
Autor:
Kruse, Janik, Lampart, Jonas
The Nelson model describes the interaction of nonrelativistic quantum particles with a relativistic quantum field of scalar bosons. Nelson rigorously demonstrated in 1964 the existence of a well-defined self-adjoint Nelson Hamiltonian by renormalisat
Externí odkaz:
http://arxiv.org/abs/2109.00230
Autor:
Binz, Tim, Lampart, Jonas
In a configuration space whose boundary can be identified with a subset of its interior, a boundary condition can relate the behaviour of a function on the boundary and in the interior. Additionally, boundary values can appear as additive perturbatio
Externí odkaz:
http://arxiv.org/abs/2103.17124