  The fundamental characteristics of soliton and chaos in nonlinear equation
are completely different. But all nonlinear equations with a soliton solution
may derive chaos. While only some equations with a chaos solution have a
soliton. The conditions of the two solutions are different. When some
parameters are certain constants, the soliton is derived; while these
parameters vary in a certain region, the bifurcation-chaos appears. It connects
a chaotic control probably. The double solutions correspond possibly to the
wave-particle duality in quantum theory, and connect the double solution theory
of the nonlinear wave mechanics. Some nonlinear equations possess soliton and
chaos, whose new meanings are discussed briefly in mathematics, physics and
particle theory.
