Related Experiment Video
Updated: Jun 10, 2025

06:25
A Real-Time Interactive System for Studying Confrontational Pursuit Behavior in Rodents
Published on: May 16, 2025
107
Extended Weyl-Wigner phase-space framework for nonlinear systems: Typical and modified prey-predator-like dynamics.
1Departamento de Física, <a href="https://ror.org/00qdc6m37">Universidade Federal de São Carlos</a>, PO Box 676, 13565-905 São Carlos, SP, Brasil.
Physical Review. E
|October 19, 2024
Summary
This study extends phase-space quantum mechanics to specific Hamiltonians, accurately capturing quantum fluctuations and revealing nonlinear dynamics in systems like quantized prey-predator models.
Area of Science:
- Quantum Mechanics
- Statistical Mechanics
- Phase-Space Formalism
Background:
- The Weyl-Wigner formalism provides a quantum mechanical description in phase space.
- Extending this formalism to more complex Hamiltonians is crucial for understanding quantum systems.
- Classical and quantum dynamics often exhibit deviations, particularly in non-stationary scenarios.
Purpose of the Study:
- To revisit and extend phase-space Weyl-Wigner quantum mechanics for Hamiltonians of the form H(q,p)=K(p)+V(q).
- To identify and quantify deviations from classical and stationary profiles using Wigner functions and currents.
- To develop a novel algorithm for treating quantum modifications in phase space.
Main Methods:
- Application of the extended phase-space Weyl-Wigner formalism to Hamiltonians with K(p) replacing p^2.
- Analysis of Wigner functions and Wigner currents for Gaussian and gamma/Laplacian distribution ensembles.
- Specialization of general results to specific Hamiltonians exhibiting nonlinear dynamics.
Main Results:
- Deviations from classical and stationary profiles were successfully identified.
- The procedure accurately accounts for quantum fluctuations compared to classical phase-space patterns.
- Nonlinear dynamics were revealed for specific Hamiltonians, including quantized prey-predator-like scenarios.
Conclusions:
- The extended phase-space Weyl-Wigner formalism effectively captures quantum fluctuations and nonlinear dynamics.
- The proposed method offers a novel algorithm for analyzing quantum modifications via Wigner currents.
- The framework is applicable to diverse systems, including those with statistical constraints.
Related Concept Videos
Linear Approximation in Time Domain
66
Nonlinear systems often require sophisticated approaches for accurate modeling and analysis, with state-space representation being particularly effective. This method is especially useful for systems where variables and parameters vary with time or operating conditions, such as in a simple pendulum or a translational mechanical system with nonlinear springs.
For a simple pendulum with a mass evenly distributed along its length and the center of mass located at half the pendulum's length,...
For a simple pendulum with a mass evenly distributed along its length and the center of mass located at half the pendulum's length,...
66
Second Order systems II
91
In an underdamped second-order system, where the damping ratio ζ is between 0 and 1, a unit-step input results in a transfer function that, when transformed using the inverse Laplace method, reveals the output response. The output exhibits a damped sinusoidal oscillation, and the difference between the input and output is termed the error signal. This error signal also demonstrates damped oscillatory behavior. Eventually, as the system reaches a steady state, the error diminishes to zero.
91
Second Order systems I
137
A servo system exemplifies a second-order system, featuring a proportional controller and load elements that ensure the output position aligns with the input position. The relationship between these components is described by a second-order differential equation. Applying the Laplace transform under zero initial conditions yields the transfer function, showing how inputs are converted to outputs in the system.
By reinterpreting the system, one can derive the closed-loop transfer function, which...
By reinterpreting the system, one can derive the closed-loop transfer function, which...
137
Linear time-invariant Systems
221
A system is linear if it displays the characteristics of homogeneity and additivity, together termed the superposition property. This principle is fundamental in all linear systems. Linear time-invariant (LTI) systems include systems with linear elements and constant parameters.
The input-output behavior of an LTI system can be fully defined by its response to an impulsive excitation at its input. Once this impulse response is known, the system's reaction to any other input can be...
The input-output behavior of an LTI system can be fully defined by its response to an impulsive excitation at its input. Once this impulse response is known, the system's reaction to any other input can be...
221
Linear Approximation in Frequency Domain
86
Linear systems are characterized by two main properties: superposition and homogeneity. Superposition allows the response to multiple inputs to be the sum of the responses to each individual input. Homogeneity ensures that scaling an input by a scalar results in the response being scaled by the same scalar.
In contrast, nonlinear systems do not inherently possess these properties. However, for small deviations around an operating point, a nonlinear system can often be approximated as linear....
In contrast, nonlinear systems do not inherently possess these properties. However, for small deviations around an operating point, a nonlinear system can often be approximated as linear....
86
Cyclic Processes And Isolated Systems
2.7K
A thermodynamic system with zero heat exchange and work is an isolated system. For these systems, the internal energy remains constant.
In the case of a non-isolated system, the change in the internal energy is zero only if the process is cyclic. A thermodynamic process is considered cyclic if the system undergoes a series of changes and returns to its initial state.
Consider a cyclic process that returns to its initial state, undergoing a four-step process. The heat transfer along each...
In the case of a non-isolated system, the change in the internal energy is zero only if the process is cyclic. A thermodynamic process is considered cyclic if the system undergoes a series of changes and returns to its initial state.
Consider a cyclic process that returns to its initial state, undergoing a four-step process. The heat transfer along each...
2.7K

