• Corpus ID: 247922675

Existence of Ground States in the Infrared-Critial Spin Boson Model

  title={Existence of Ground States in the Infrared-Critial Spin Boson Model},
  author={Benjamin Hinrichs},
We review recent results on the existence of ground states for the infrared-critical spin boson model, which describes the interaction of a massless bosonic field with a two-state quantum system. Explicitly, we derive a critical coupling λc > 0 such that the spin boson model exhibits a ground state for coupling constants λ with |λ| < λc. The proof combines a Feynman– Kac–Nelson formula for the spin boson model with external magnetic field, a 1D-Ising model correlation bound and a compactness… 



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