HOME

TheInfoList



OR:

In the theory of
integrable systems In mathematics, integrability is a property of certain dynamical systems. While there are several distinct formal definitions, informally speaking, an integrable system is a dynamical system with sufficiently many conserved quantities, or first i ...
, a compacton, introduced in , is a
soliton In mathematics and physics, a soliton or solitary wave is a self-reinforcing wave packet that maintains its shape while it propagates at a constant velocity. Solitons are caused by a cancellation of nonlinear and dispersive effects in the mediu ...
with
compact support In mathematics, the support of a real-valued function f is the subset of the function domain containing the elements which are not mapped to zero. If the domain of f is a topological space, then the support of f is instead defined as the smal ...
. An example of an equation with compacton solutions is the generalization : u_t+(u^m)_x+(u^n)_=0\, of the Korteweg–de Vries equation (KdV equation) with ''m'', ''n'' > 1. The case with ''m'' = ''n'' is the
Rosenau–Hyman equation The Rosenau–Hyman equation or ''K''(''n'',''n'') equation is a KdV-like equation having compacton solutions. This nonlinear partial differential equation In mathematics, a partial differential equation (PDE) is an equation which imposes rel ...
as used in their 1993 study; the case ''m'' = 2, ''n'' = 1 is essentially the KdV equation.


Example

The equation : u_t+(u^2)_x+(u^2)_=0 \, has a
travelling wave In physics, mathematics, and related fields, a wave is a propagating dynamic disturbance (change from equilibrium) of one or more quantities. Waves can be periodic, in which case those quantities oscillate repeatedly about an equilibrium (re ...
solution given by : u(x,t) = \begin \dfrac\cos^2((x-\lambda t)/4) & \text, x - \lambda t, \le 2\pi, \\ \\ 0 & \text, x - \lambda t, \ge 2\pi. \end This has compact support in ''x'', and so is a compacton.


See also

*
Peakon In the theory of integrable systems, a peakon ("peaked soliton") is a soliton with discontinuous first derivative; the wave profile is shaped like the graph of the function e^. Some examples of non-linear partial differential equations with (multi-) ...
*
Vector soliton In physical optics or wave optics, a vector soliton is a solitary wave with multiple components coupled together that maintains its shape during propagation. Ordinary solitons maintain their shape but have effectively only one (scalar) polarizatio ...


References

* * *{{citation, title=Exact discrete breather compactons in nonlinear Klein-Gordon lattices , last1=Comte , first1=Jean-Christophe , journal=
Physical Review E ''Physical Review E'' is a peer-reviewed, scientific journal, published monthly by the American Physical Society. The main field of interest is collective phenomena of many-body systems. It is currently edited by Uwe C. Täuber. While original ...
, publisher=American Physical Society , year=2002, volume=65 , issue=6 , pages=067601, doi=10.1103/PhysRevE.65.067601 , pmid=12188877 , bibcode=2002PhRvE..65f7601C Solitons