The Massless Nelson Hamiltonian and Its Domain

  title={The Massless Nelson Hamiltonian and Its Domain},
  author={Julian Schmidt},
  journal={Springer INdAM Series},
In the theory of point interactions, one is given a formal expression for a quantum mechanical Hamiltonian. The interaction terms of the Hamiltonian are singular: they can not be rigorously defined as a perturbation (in the operator or form sense) of an unperturbed free operator. A similar situation occurs in Quantum Field Theory, where it is known as the ultraviolet problem. Recently, it was shown that some of the tools used in the context of point interactions can be adapted to solve the… 
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