Related Concept Videos
Linear time-invariant Systems
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...
Second Order systems I
By reinterpreting the system, one can derive the closed-loop transfer function, which...
Classification of Systems-I
Homogeneity dictates that if an input x(t) is multiplied by a constant c, the output y(t) is multiplied by the same constant. Mathematically, this is expressed as:
Second Order systems II
Dimensionless Groups in Fluid Mechanics
First Law: Particles in One-dimensional Equilibrium
You might also read
Related Articles
Articles linked to this work by shared authors, journal, and citation graph.
Combining machine learning and data assimilation to forecast dynamical systems from noisy partial observations.
Mesoscopic model reduction for the collective dynamics of sparse coupled oscillator networks.
Model reduction for the collective dynamics of globally coupled oscillators: From finite networks to the thermodynamic limit.
Introduction to Focus Issue: Linear response theory: Potentials and limits.
Chaos in networks of coupled oscillators with multimodal natural frequency distributions.
Gap junction architecture and synchronization clusters in the thalamic reticular nuclei.
Exact computation of Lyapunov exponents via system parameters in multi-triangle chaotic maps: Bifurcation analysis and circuit realization.
Integrating score-based generative modeling and neural ODEs for accurate representation of multiscale chaotic dynamics.
A data-driven tuberculosis model with behavioral changes and saturated treatment: Optimal control and cost-effectiveness study.
Breathers, rational solutions, and their exact physical spectra in F = 1 spinor Bose-Einstein condensates.
Related Experiment Video
Updated: Jan 3, 2026

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Linear response for macroscopic observables in high-dimensional systems.
Caroline L Wormell1, Georg A Gottwald1
1School of Mathematics and Statistics, The University of Sydney, Sydney, New South Wales 2006, Australia.
Linear response theory (LRT) explains chaotic system behavior, but its mechanism in complex systems is unclear. This study reveals how macroscopic observables in coupled systems exhibit LRT via self-generated noise, even when microscopic parts do not.
Area of Science:
- Statistical mechanics
- Dynamical systems theory
- Nonlinear dynamics
Background:
- Linear response theory (LRT) predicts chaotic system behavior but doesn't apply universally.
- The mechanism for macroscopic observables in complex dissipative chaotic systems exhibiting LRT, despite microscopic violations, is poorly understood.
- High-dimensional coupled deterministic dynamical systems with mean-field coupling present a complex scenario for LRT.
Purpose of the Study:
- To provide a comprehensive understanding of linear response in macroscopic observables of high-dimensional coupled deterministic dynamical systems.
- To derive conditions under which LRT holds for these systems, both in finite dimensions and the thermodynamic limit.
- To investigate the role of self-generated noise and emergent dynamics in the applicability of LRT.
Main Methods:
- Derivation of stochastic reductions for macroscopic observables from microscopic system statistics.
- Analysis of conditions for LRT in finite-dimensional systems and the thermodynamic limit.
- Numerical evidence and analytical intuition to support theoretical findings.
Main Results:
- Linear response in large, finite systems is induced by self-generated noise.
- Demonstration of macroscopic LRT in the thermodynamic limit, even when microscopic subsystems violate LRT.
- Identification of a converse case where macroscopic observables violate LRT despite microscopic subsystems adhering to it, linked to emergent dynamics.
Conclusions:
- Self-generated noise is a key mechanism enabling linear response in macroscopic observables of large, coupled chaotic systems.
- The applicability of LRT to macroscopic observables is not solely dependent on the microscopic constituents' adherence to it.
- Emergent dynamics in macroscopic observables can lead to deviations from LRT, even in systems composed of individually linear-responsive parts.

