Search Results - "Lampart, Jonas"

Hamiltonians for Polaron Models with Subcritical Ultraviolet Singularities by Lampart, Jonas

“…We treat the ultraviolet problem for polaron-type models in nonrelativistic quantum field theory. Assuming that the dispersion relations of particles and the…”
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The Resolvent of the Nelson Hamiltonian Improves Positivity by Lampart, Jonas

“…We give a new proof that the resolvent of the renormalised Nelson Hamiltonian at fixed total momentum P improves positivity in the (momentum)…”
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Dynamics of a Tracer Particle Interacting with Excitations of a Bose–Einstein Condensate by Lampart, Jonas, Pickl, Peter

“…We consider the quantum dynamics of a large number N of interacting bosons coupled a tracer particle, i.e. a particle of another kind, on a torus. We assume…”
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On the Global Minimum of the Energy–Momentum Relation for the Polaron by Lampart, Jonas, Mitrouskas, David, Myśliwy, Krzysztof

“…For the Fröhlich 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…”
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Equality of Magnetization and Edge Current for Interacting Lattice Fermions at Positive Temperature by Lampart, Jonas, Moscolari, Massimo, Teufel, Stefan, Wessel, Tom

“…We prove that the magnetization is equal to the edge current in the thermodynamic limit for a large class of models of lattice fermions with finite-range…”
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Semi-Classical Dirac Vacuum Polarisation in a Scalar Field by Lampart, Jonas, Lewin, Mathieu

“…We study vacuum polarisation effects of a Dirac field coupled to an external scalar field and derive a semi-classical expansion of the regularised vacuum…”
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Schriftliches mathematisches Argumentieren in zwei unterschiedlichen Inhaltsbereichen in den Jahrgangsstufen 4–6 by Brunner, Esther, Lampart, Jonas, Jullier, Romaine

“…Zusammenfassung Im Rahmen einer Studie zum schriftlichen mathematischen Argumentieren wurde untersucht, wie Schülerinnen und Schüler der Jahrgangsstufen 4–6 (…”
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A Nonrelativistic Quantum Field Theory with Point Interactions in Three Dimensions by Lampart, Jonas

“…We construct a Hamiltonian for a quantum-mechanical model of nonrelativistic particles in three dimensions interacting via the creation and annihilation of a…”
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Mathematikunterricht in jahrgangsübergreifenden Klassen der Grundschule in der Schweiz und in Deutschland: eine vergleichende Studie by Brunner, Esther, Gasteiger, Hedwig, Lampart, Jonas, Schreieder, Kathrin

“…Im Rahmen einer Befragung von Lehrpersonen aus jahrgangsübergreifenden Klassen in einem Schweizer Kanton und in einer Region Bayerns wurden Gestaltungsmerkmale…”
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A Lower Bound on the Critical Momentum of an Impurity in a Bose–Einstein Condensate by Hinrichs, Benjamin, Lampart, Jonas

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On Nelson-Type Hamiltonians and Abstract Boundary Conditions by Lampart, Jonas, Schmidt, Julian

“…We construct Hamiltonians for systems of nonrelativistic particles linearly coupled to massive scalar bosons using abstract boundary conditions. The…”
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The adiabatic limit of Schrödinger operators on fibre bundles by Lampart, Jonas, Teufel, Stefan

“…We consider Schrödinger operators H = - Δ g ε + V on a fibre bundle M → π B with compact fibres and a metric g ε that blows up directions perpendicular to the…”
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The Adiabatic Limit of the Connection Laplacian by Haag, Stefan, Lampart, Jonas

“…We study the behaviour of Laplace-type operators H on a complex vector bundle E → M in the adiabatic limit of the base space. This space is a fibre bundle M →…”
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A Many-Body RAGE Theorem by Lampart, Jonas, Lewin, Mathieu

“…We prove a generalized version of the RAGE theorem for N -body quantum systems. The result states that only bound states of systems with 0 ⩽ n ⩽ N particles…”
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On the global minimum of the energymomentum relation for the polaron by Lampart, Jonas, Mitrouskas, David, Myśliwy, Krzysztof

“…For the Fröhlich 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…”
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Convergence of nodal sets in the adiabatic limit by Lampart, Jonas

“…We study the nodal sets of non-degenerate eigenfunctions of the Laplacian on fibre bundles π : M → B in the adiabatic limit. This limit consists in considering…”
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Particle Creation at a Point Source by Means of Interior-Boundary Conditions by Lampart, Jonas, Schmidt, Julian, Teufel, Stefan, Tumulka, Roderich

“…We consider a way of defining quantum Hamiltonians involving particle creation and annihilation based on an interior-boundary condition (IBC) on the wave…”
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Generalised Quantum Waveguides by Haag, Stefan, Lampart, Jonas, Teufel, Stefan

“…We study general quantum waveguides and establish explicit effective Hamiltonians for the Laplacian on these spaces. A conventional quantum waveguide is an ϵ…”
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The Dirac–Klein–Gordon system in the strong coupling limit by Lampart, Jonas, Le Treust, Loïc, Rota Nodari, Simona, Sabin, Julien

“…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…”
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Hamiltonians for polaron models with subcritical ultraviolet singularities by Lampart, Jonas

“…Annales Henri Poincare 24 (2023) We treat the ultraviolet problem for polaron-type models in nonrelativistic quantum field theory. Assuming that the dispersion…”
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