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. 
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8 Citations

8 Citations

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