# Dynamical system
A dynamical system is a mathematical formalization of state evolution over time, typically via a [[Differential_equation|differential equation]], map, or flow in [[Phase_space|phase space]]. Trajectories, [[Attractor|attractors]], bifurcations, Lyapunov stability, chaos (sensitive dependence), ergodicity, and structural stability characterize continuous, discrete, stochastic, or hybrid systems across [[Physics|physics]], [[Biology|biology]], and [[Engineering|engineering]].
<!-- LEGACYSIM:BEGIN v1.5 — generated by g03_mint_wave.py; three.js first; do not hand-edit inside -->
## Microsims (promoted from legacy — three.js first)
### MicroSim spec
- **Recommended sim type:** [[Phase_space|phase space]] / [[Attractor|attractor]]
- **Microsimmability score:** 88/100
- **Layout:** drawing region (canvas) on top; control region (sliders/buttons) below.
### Parameters (tunable controls)
- `Parameter a`
- `Time step`
- `Initial condition`
### What animates
A state evolves step by step along a trajectory that bends as the parameters change.
### Learning objective
Show how an update rule moves a system's state through time.
<!-- LEGACYSIM:END -->
<!-- GIFPLATE:BEGIN v1.0 g16 — Commons hotlink; do not hand-edit inside -->
## Images
<figure class="wt-gifplate">
<img src="https://commons.wikimedia.org/wiki/Special:FilePath/Lorenz_attractor.gif" alt="Attractor Dynamics" loading="lazy" decoding="async">
<figcaption><strong>Attractor Dynamics</strong> — Watch a trajectory trace a butterfly-shaped path. This is the Lorenz attractor—how deterministic rules generate endlessly complex, bounded motion.<br>
<span class="wt-credit">Wikimedia Commons · <strong>licence pending verification</strong> (run <code>g17_gif_verify.py</code> on a networked lane) · <a href="https://commons.wikimedia.org/wiki/File:Lorenz_attractor.gif">Details</a></span></figcaption>
</figure>
*The hub concept of [[PORTAL_Dynamical_system]], and this page has no interactive build yet — the plate carries it.*
<!-- GIFPLATE:END -->
## Reveal
%%REVEAL:p5%%
%%REVEAL:three%%
---
*Concept aligned with [Wikipedia](https://en.wikipedia.org/wiki/Dynamical_system); adapted text, where present, is licensed [CC BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0/).*
## Overview
Continuous flow is written as an [[Ordinary_differential_equation|ordinary differential equation]] or [[Partial_differential_equation|partial differential equation]]; discrete evolution as iterated maps and the [[Cellular_automaton|cellular automaton]]. [[Bifurcation_theory|Bifurcation theory]] tracks qualitative change, [[Chaos_theory|chaos theory]] follows [[Edward_Norton_Lorenz|Edward Norton Lorenz]] into sensitive dependence, and [[Statistical_mechanics|statistical mechanics]] treats ensembles of trajectories. The geometry threads through [[Fractal|fractals]], [[Topology|topology]], and [[Functional_analysis|functional analysis]].
Applications feed [[Control_theory|control theory]], [[Population_dynamics|population dynamics]], [[System_dynamics|system dynamics]], the [[Dissipative_system|dissipative system]] and [[Self-organized_criticality|self-organized criticality]], [[Network_theory|network]] dynamics, and modern [[Machine_learning|machine learning]], making the [[Mathematical_model|mathematical model]] of time-evolution the shared grammar of [[Systems_theory|systems theory]].
## Wikipedia : Wikitube
**Strict pair:** [Wikipedia](https://en.wikipedia.org/wiki/Dynamical_system) : [Wikitube](https://en.wikitube.io/wiki/Dynamical_system)
## Previous hub tags
Hubs: `Systems`. Portals: [[PORTAL_Systems]], [[PORTAL_Dynamical_system]].