Jozsef Lorinczi, Robert A. Minlos, Herbert Spohn Infrared regular representation of the three dimensional massless Nelson model (170K, postscript) ABSTRACT. We prove that in the Euclidean representation of the three dimensional massless Nelson model the t = 0 projection of the interacting measure is absolutely continuous with respect to a Gaussian measure with suitably adjusted mean. We also determine the Hamiltonian in the Fock space over this Gaussian measure space.