ar X iv : m at h - ph / 0 20 90 10 v 1 5 S ep 2 00 2 DECOHERENCE AND INFRARED DIVERGENCE 1 Joachim Kupsch
نویسنده
چکیده
The dynamics of a particle which is linearly coupled to the environment of a Boson field is investigated. For velocity coupling and for local (position) coupling the reduced dynamics of the particle induces superselection rules for the momentum, if the Boson field is infrared divergent. Thereby the Hamiltonian of the total system remains bounded from below.
منابع مشابه
The role of infrared divergence for decoherence
Continuous and discrete superselection rules induced by the interaction with the environment are investigated for a class of exactly soluble Hamiltonian models. The environment is given by a Boson field. Stable superselection sectors can only emerge if the low frequences dominate and the ground state of the Boson field disappears due to infrared divergence. The models allow uniform estimates of...
متن کاملExactly soluble models of decoherence
Superselection rules induced by the interaction with the environment are investigated with the help of exactly soluble Hamiltonian models. Starting from the examples of Araki and of Zurek more general models with scattering are presented for which the projection operators onto the induced superselection sectors do no longer commute with the Hamiltonian. The example of an environment given by a ...
متن کاملSuperselection rules induced by infrared divergence
Superselection rules induced by the interaction with a mass zero Boson field are investigated for a class of exactly soluble Hamiltonian models. The calculations apply as well to discrete as to continuous superselection rules. The initial state (reference state) of the Boson field is either a normal state or a KMS state. The superselection sectors emerge if and only if the Boson field is infrar...
متن کاملQuantum Metrology with Lattice-confined Ultracold Sr Atoms
Quantum state engineering of ultracold matter and precise control of optical fields have together allowed accurate measurement of light-matter interactions for applications in precision tests of fundamental physics. State-of-the-art lasers maintain optical phase coherence over one second. Optical frequency combs distribute this optical phase coherence across the entire visible and infrared part...
متن کاملCoarse-grained field wave function in Stochastic inflation
In the framework of inflationary cosmology I study the wave function for the matter field fluctuations in the infrared sector. This fluctuations are described by a coarse-grained field which takes into account only the modes with wavelength much bigger than the size of the Hubble horizon. The case of a power-law expanding universe is studied. I find that decoherence of phasespace (χcg, Pcg) in ...
متن کامل