Dynamical reduction models

  title={Dynamical reduction models},
  author={Angelo Bassi and Giancarlo Ghirardi},
  journal={Physics Reports},
A Flea on Schroedinger's Cat
We propose a technical reformulation of the measurement problem of quantum mechanics, which is based on the postulate that the final state of a measurement is classical. Unlike the usual formulation
In Praise and in Criticism of the Model of Continuous Spontaneous Localization of the Wave-Function
Different attempts to solve the measurement problem of the quantum mechanics (QM) by denying the collapse principle, and replacing it with changes in the quantum formalism, failed because the changes
Obtaining continuous collapse models in formulations of Quantum Mechanics with trajectories
Bohmian Mechanics is a formulation of Quantum Mechanics where particles follow space-time trajectories according to a law determined by the wave function. For an isolated system, such a function
Quantum collapse dynamics with attractive densities
We discuss a model of spontaneous collapse of the quantum state that does not require adding any stochastic processes to the standard dynamics. The additional ingredient with respect to the wave
A Refined Propensity Account for GRW Theory
This paper proposes a novel and complete dispositional account of GRW, based on what I call spontaneous weighted multi-track propensities, and claims that such an account can satisfy both of the authors' desiderata.
Generally covariant dynamical reduction models and the Hadamard condition
We recall and review earlier work on dynamical reduction models, both non-relativistic and relativistic, and discuss how they may relate to suggestions which have been made (including the
Symmetry aspects in emergent quantum mechanics
We discuss an explicit realization of the dissipative dynamics anticipated in the proof of 't Hooft's existence theorem, which states that 'For any quantum system there exists at least one
Relaxation of quantum states under energy perturbations
  • D. Brody, L. Hughston, J. Syroka
  • Physics
    Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences
  • 2003
The energy‐based stochastic extension of the Schrödinger equation is perhaps the simplest mathematically rigorous and physically plausible model for the reduction of the wave function. In this
Modified Schrödinger dynamics with attractive densities
AbstractThe linear Schrödinger equation does not predict that macroscopic bodies should be located at one place only, or that the outcome of a measurement shoud be unique. Quantum mechanics textbooks


Describing the macroscopic world: Closing the circle within the dynamical reduction program
With reference to recently proposed theoretical models accounting for reduction in terms of a unified dynamics governing all physical processes, we analyze the problem of working out a worldview
Bohmian Mechanics Revisited
We consider the problem of whether there are deterministic theories describing the evolution of an individual physical system in terms of the definite trajectories of its constituent particles and
Dynamical reduction models with general Gaussian noises
It is proved that the effect of replacing in stochastic differential equations leading to the dynamical collapse of the state vector, white-noise Stochastic processes with nonwhite ones with the aim of overcoming intractable divergences in relativistic models.
Operations involving momentum variables in non-Hamiltonian evolution equations
SummaryNon-Hamiltonian evolution equations have been recently considered for the description of various physical processes. Among these types of equations the class which has been more extensively
Unified dynamics for microscopic and macroscopic systems.
A modified quantum dynamics for the description of macroscopic objects is constructed and it is shown that it forbids the occurrence of linear superpositions of states localized in far-away spatial regions and induces an evolution agreeing with classical mechanics.
Decay theory of unstable quantum systems
The present review article is aimed at a clear formulation of the basic problematics of the decay and at a description of the various recent attempts to solve this delicate problem, illustrating both
Spontaneous localizations of the wave function and classical behavior
We investigate and develop further two models, the GRW model and the K model, in which the Schrödinger evolution of the wave function is spontaneously and repeatedly interrupted by random,
Generalized stochastic Schrödinger equations for state vector collapse
A number of authors have proposed stochastic versions of the Schrodinger equation, either as effective evolution equations for open quantum systems or as alternative theories with an intrinsic