In mathematics, the master stability function is a tool used to analyze the
stability
Stability may refer to:
Mathematics
*Stability theory, the study of the stability of solutions to differential equations and dynamical systems
** Asymptotic stability
** Linear stability
** Lyapunov stability
** Orbital stability
** Structural sta ...
of the synchronous state in a
dynamical system
In mathematics, a dynamical system is a system in which a function describes the time dependence of a point in an ambient space. Examples include the mathematical models that describe the swinging of a clock pendulum, the flow of water in ...
consisting of many identical systems which are coupled together, such as the
Kuramoto model
The Kuramoto model (or Kuramoto–Daido model), first proposed by , is a mathematical model used to describing synchronization. More specifically, it is a model for the behavior of a large set of coupled oscillators. Its formulation was motivated b ...
.
The setting is as follows. Consider a system with
identical oscillators. Without the coupling, they evolve according to the same
differential equation
In mathematics, a differential equation is an equation that relates one or more unknown functions and their derivatives. In applications, the functions generally represent physical quantities, the derivatives represent their rates of change, an ...
, say
where
denotes the state of oscillator
. A synchronous state of the system of oscillators is where all the oscillators are in the same state.
The coupling is defined by a coupling strength
, a matrix
which describes how the oscillators are coupled together, and a function
of the state of a single oscillator. Including the coupling leads to the following equation:
:
It is assumed that the row sums
vanish so that the manifold of synchronous states is neutrally stable.
The master stability function is now defined as the function which maps the complex number
to the greatest
Lyapunov exponent of the equation
:
The synchronous state of the system of coupled oscillators is stable if the master stability function is negative at
where
ranges over the eigenvalues of the coupling matrix
.
References
* .
* {{citation , last1 = Pecora , first1 = Louis M. , last2 = Carroll , first2 = Thomas L. , title = Master stability functions for synchronized coupled systems , journal = Physical Review Letters , year = 1998 , volume = 80 , issue = 10 , pages = 2109–2112 , doi = 10.1103/PhysRevLett.80.2109 , bibcode = 1998PhRvL..80.2109P .
Dynamical systems