scholarly journals On the Existence and Robustness of Steady Position-Momentum Correlations for Time-Dependent Quadratic Systems

2012 ◽  
Vol 2012 ◽  
pp. 1-16
Author(s):  
M. Gianfreda ◽  
G. Landolfi
Keyword(s):  
Quantum Dynamics ◽  
Quantum Correlations ◽  
Time Dependent ◽  
Quantum Decoherence ◽  
Linear Superposition ◽  
Time Intervals ◽  
One Dimensional ◽  
The One ◽  
Basic Features ◽  
Hamiltonian Operators

We discuss conditions giving rise to stationary position-momentum correlations among quantum states in the Fock and coherent basis associated with the natural invariant for the one-dimensional time-dependent quadratic Hamiltonian operators such as the Kanai-Caldirola Hamiltonian. We also discuss some basic features such as quantum decoherence of the wave functions resulting from the corresponding quantum dynamics of these systems that exhibit no timedependence in their quantum correlations. In particular, steady statistical momentum averages are seen over well-defined time intervals in the evolution of a linear superposition of the basis states of modified exponentially damped mass systems.

A new algorithm for numerical modelling of impurity transport in the frame of statistically homogeneous sharply contrasting media

2019 ◽  
Vol 34 (6) ◽  
pp. 339-351 ◽  
Author(s):  
Petr S. Kondratenko ◽  
Leonid V. Matveev ◽  
Alexander D. Vasiliev
Keyword(s):  
Numerical Modelling ◽  
Contaminant Transport ◽  
Integral Kernel ◽  
Time Intervals ◽  
One Dimensional ◽  
Time Representation ◽  
Impurity Transport ◽  
The One ◽  
Analytical Expressions ◽  
Good Agreement

Abstract A new method is developed to calculate characteristics of contaminant transport (including non-classical regimes) in statistically homogeneous sharply contrasting media. A transport integro-differential equation in the space-time representation is formulated on the basis of the model earlier proposed by one of the authors (L. M.). Analytical expressions for transport characteristics in limiting time intervals in the one-dimensional case are derived. An interpolation form is proposed for the integral kernel of the transport equation. On a basis of this expression, an algorithm is developed for numerical modelling the contaminant transport in statistically homogeneous sharply contrasting media. Trial numerical 1D calculations are performed based on this algorithm. Good agreement was found between the numerical simulation results and the asymptotic analytical expressions.

scholarly journals On combined optical solitons of the one-dimensional Schrödinger’s equation with time dependent coefficients

Open Physics ◽  
2016 ◽  
Vol 14 (1) ◽  
pp. 65-68 ◽  
Author(s):  
Bulent Kilic ◽  
Mustafa Inc ◽  
Dumitru Baleanu
Keyword(s):  
Soliton Solutions ◽  
First Integral ◽  
Optical Solitons ◽  
Time Dependent ◽  
Ansatz Method ◽  
One Dimensional ◽  
Optical Metamaterials ◽  
Schrödinger’S Equation ◽  
The One ◽  
Schrödinger's Equation

AbstractThis paper integrates dispersive optical solitons in special optical metamaterials with a time dependent coefficient. We obtained some optical solitons of the aforementioned equation. It is shown that the examined dependent coefficients are affected by the velocity of the wave. The first integral method (FIM) and ansatz method are applied to reach the optical soliton solutions of the one-dimensional nonlinear Schrödinger’s equation (NLSE) with time dependent coefficients.

scholarly journals EMPTINESS FORMATION PROBABILITY AND QUANTUM KNIZHNIK-ZAMOLODCHIKOV EQUATION

2004 ◽  
Vol 19 (supp02) ◽  
pp. 57-81
Author(s):  
H. E. BOOS ◽  
V. E. KOREPIN ◽  
F. A. SMIRNOV
Keyword(s):  
Quantum Correlations ◽  
Zero Magnetic Field ◽  
Heisenberg Antiferromagnet ◽  
Zero Temperature ◽  
One Dimensional ◽  
Formation Probability ◽  
Antiferromagnetic Ground State ◽  
A New Technique ◽  
The One ◽  
Zamolodchikov Equation

We consider the one-dimensional XXX spin 1/2 Heisenberg antiferromagnet at zero temperature and zero magnetic field. We are interested in a probability of a formation of a ferromagnetic string P(n) in the antiferromagnetic ground-state. We call it emptiness formation probability [EFP]. We suggest a new technique for computation of the EFP in the inhomogeneous case. It is based on the quantum Knizhnik-Zamolodchikov equation [qKZ]. We calculate EFP for n≤6 for the inhomogeneous case. The homogeneous limit confirms our hypothesis about the relation of quantum correlations and number theory. We also make a conjecture about a structure of EFP for arbrary n.

RELAXATION AND TRANSIENTS IN A TIME-DEPENDENT LOGISTIC MAP

2002 ◽  
Vol 12 (07) ◽  
pp. 1667-1674 ◽  
Author(s):  
EDSON D. LEONEL ◽  
J. KAMPHORST LEAL DA SILVA ◽  
S. OLIFFSON KAMPHORST
Keyword(s):  
Control Parameter ◽  
Logistic Map ◽  
Period Doubling ◽  
Time Dependent ◽  
One Dimensional ◽  
Stability Period ◽  
The One ◽  
Exchange Of Stability ◽  
Small Periodic ◽  
Scaling Arguments

We study the one-dimensional logistic map with control parameter perturbed by a small periodic function. In the pure constant case, scaling arguments are used to obtain the exponents related to the relaxation of the trajectories at the exchange of stability, period-doubling and tangent bifurcations. In particular, we evaluate the exponent z which describes the divergence of the relaxation time τ near a bifurcation by the relation τ ~ | R - Rc |-z. Here, R is the control parameter and Rc is its value at the bifurcation. In the time-dependent case new attractors may appear leading to a different bifurcation diagram. Beside these new attractors, complex attractors also arise and are responsible for transients in many trajectories. We obtain, numerically, the exponents that characterize these transients and the relaxation of the trajectories.

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