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Related papers: Dynamical typicality of quantum expectation values

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Dynamical typicality refers to the property that two pure states, which initially exhibit (almost) the same expectation value for some given observable $A$, are very likely to exhibit also very similar expectation values when evolving in…

Statistical Mechanics · Physics 2018-06-19 Peter Reimann

We consider all pure or mixed states of a quantum many-body system which exhibit the same, arbitrary but fixed measurement outcome statistics for several commuting observables. Taking those states as initial conditions, which are then…

Statistical Mechanics · Physics 2019-04-08 B. N. Balz , J. Richter , J. Gemmer , R. Steinigeweg , P. Reimann

Dynamic equations concerning physical expectation values have been examined in terms of the real Hilbert space approach to quantum mechanics. The considered cases involve complex wave functions, as well as quaternionic wave functions. The…

Quantum Physics · Physics 2025-09-19 Sergio Giardino

The typicality approach and the Hilbert space averaging method as its technical manifestation are important concepts of quantum statistical mechanics. Extensively used for expectation values we extend them in this paper to transition…

Quantum Physics · Physics 2020-08-25 Nico Hahn , Thomas Guhr , Daniel Waltner

The expected return time to the original state is a key concept characterizing systems obeying both classical or quantum dynamics. We consider iterated open quantum dynamical systems in finite dimensional Hilbert spaces, a broad class of…

Quantum Physics · Physics 2015-04-16 P. Sinkovicz , Z. Kurucz , T. Kiss , J. K. Asbóth

Given a physical quantum system described by a Hilbert H, for any bounded quantum observable (a bounded self-adjoint operator) T it is possible to define several ''hidden observable'' functions f:H->R associated to T and for any quantum…

Quantum Physics · Physics 2007-11-18 Antonio Cassa

Quantum typicality refers to the phenomenon that the expectation values of any given observable are nearly identical for the overwhelming majority of all normalized vectors in a sufficiently high-dimensional Hilbert (sub-)space. As a…

Statistical Mechanics · Physics 2025-10-09 Peter Reimann , Nicolas Nessi

We constructed the representation of contextual probabilistic dynamics in the complex Hilbert space. Thus dynamics of the wave function can be considered as Hilbert space projections of realistic dynamics in a ``prespace''. The basic…

Quantum Physics · Physics 2015-06-26 Andrei Yu. Khrennikov

Consider a mixed quantum mechanical state, describing a statistical ensemble in terms of an arbitrary density operator $\rho$ of low purity, $\tr\rho^2\ll 1$, and yielding the ensemble averaged expectation value $\tr(\rho A)$ for any…

Statistical Mechanics · Physics 2009-11-13 Peter Reimann

We obtain exact analytic expressions for a class of functions expressed as integrals over the Haar measure of the unitary group in d dimensions. Based on these general mathematical results, we investigate generic dynamical properties of…

Quantum Physics · Physics 2013-04-30 Manuel Gessner , Heinz-Peter Breuer

The purpose of the paper is to study the foundations of the main axioms of Quantum Mechanics. From a general study of the mathematical properties of the models used in Physics to represent systems, we prove that the states of a system can…

Mathematical Physics · Physics 2015-07-02 Jean Claude Dutailly

We explore how the expectation values $\langle\psi |A| \psi\rangle$ of a largely arbitrary observable $A$ are distributed when normalized vectors $|\psi\rangle$ are randomly sampled from a high dimensional Hilbert space. Our analytical…

Statistical Mechanics · Physics 2019-01-18 Peter Reimann , Jochen Gemmer

We study the emergence of typicality in classical systems with a large number of binary state variables. We show analytically that for sufficiently large subsets of the complete state space, state functions which can be associated with…

Statistical Mechanics · Physics 2025-03-12 Nicolas Nessi

A general quantum constraint of the form $C= - \partial_T^2 \otimes B - I\otimes H$ (realized in particular in Loop Quantum Cosmology models) is studied. Group Averaging is applied to define the Hilbert space of solutions and the relational…

General Relativity and Quantum Cosmology · Physics 2010-04-14 Wojciech Kaminski , Jerzy Lewandowski , Tomasz Pawlowski

We consider the quantum dynamical evolution of a fully-connected quantum system subjected to random projective measurements and study the first detection time of an extended subspace of the Hilbert space. Exact analytical expressions are…

Quantum Physics · Physics 2026-01-26 Giuseppe Del Vecchio Del Vecchio , Satya N. Majumdar

The dynamics of a quantum system, undergoing unitary evolution and continuous monitoring, can be described in term of quantum trajectories. Although the averaged state fully characterises expectation values, the entire ensamble of…

Quantum Physics · Physics 2023-05-09 Guglielmo Lami , Alessandro Santini , Mario Collura

We discuss some aspects related to the so-called Hilbert space Average Method, as an alternative to describe the dynamics of open quantum systems. First we present a derivation of the method which does not make use of the algebra satisfied…

Quantum Physics · Physics 2009-01-19 A. Perez

The conventional, time-dependent Schroedinger equation describes only unidirectional time evolution of the state of a physical system, i.e., forward or, less commonly, backward. This paper proposes a generalized quantum dynamics for the…

Quantum Physics · Physics 2008-11-26 G. E. Hahne

This paper proposes an approach to interpreting quantum expectation values that may help address the quantum measurement problem. Quantum expectation values are usually calculated via Hilbert space inner products and, thereby, differently…

Quantum Physics · Physics 2025-12-09 Simon Friederich

Investigation on foundational aspects of quantum statistical mechanics recently entered a renaissance period due to novel intuitions from quantum information theory and to increasing attention on the dynamical aspects of single quantum…

Quantum Physics · Physics 2010-07-22 Barbara Fresch , Giorgio J. Moro
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