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Article
Open AccessOn Lieb–Robinson Bounds for a Class of Continuum Fermions
We consider the quantum dynamics of a many-fermion system in \({{\mathbb {R}}}^d\) ...
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Open AccessGround States for Infrared Renormalized Translation-Invariant Non-Relativistic QED
We consider a translation-invariant Pauli–Fierz model describing a non-relativistic charged quantum mechanical particle interacting with the quantized electromagnetic field. The charged particle may be spinles...
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Open AccessFKN Formula and Ground State Energy for the Spin Boson Model with External Magnetic Field
We consider the spin boson model with external magnetic field. We prove a path integral formula for the heat kernel, known as Feynman–Kac–Nelson (FKN) formula. We use this path integral representation to expre...
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Open AccessOn Existence of Ground States in the Spin Boson Model
We show the existence of ground states in the massless spin boson model without any infrared regularization. Our proof is non-perturbative and relies on a compactness argument. It works for arbitrary values of...
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Article
Open AccessThermal Ionization for Short-Range Potentials
We study a concrete model of a confined particle in form of a Schrödinger operator with a compactly supported smooth potential coupled to a bosonic field at positive temperature. We show, that the model exhibi...