# On Existence of Ground States in the Spin Boson Model

@article{Hasler2021OnEO, title={On Existence of Ground States in the Spin Boson Model}, author={David Hasler and Benjamin Hinrichs and Oliver Siebert}, journal={Communications in Mathematical Physics}, year={2021}, volume={388}, pages={419 - 433} }

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 the coupling constant under the hypothesis that the second derivative of the ground state energy as a function of a constant external magnetic field is bounded.

## 8 Citations

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