In this paper, a type of fully nonlinear Sine-Gordon equations and the approximate Sine-Gordon equation (under the condition: |up|is very small) are studied.Through proper transformation, some initial value problems of many equations with special nonlinear terms are solved by the Adomian decomposition method and some exact solutions: kink solution ,compacton solution, multi-compacton solution, ...

For free Klein-Gordon fields, we construct a one-parameter family of conserved current densities J a , with a ∈ (−1, 1), and use the latter to yield a manifestly covariant expression for the most general positive-definite and Lorentz-invariant inner product on the space of solutions of the Klein-Gordon equation. Employing a recently developed method of constructing the Hilbert space and observa...

A relativistic analogue of the quantum adiabatic approximation is developed for Klein-Gordon fields minimally coupled to electromagnetism, gravity and an arbitrary scalar potential. The corresponding adiabatic dynamical and geometrical phases are calculated. The method introduced in this paper avoids the use of an inner product on the space of solutions of the Klein-Gordon equation. Its practic...

We prove a formula conjectured by Ahrens, Gordon, and McMa-hon for the number of interior points for a point connguration in R d. Our method is to show that the formula can be interpreted as a sum of Euler characteristics of certain complexes associated with the point connguration, and then compute the homology of these complexes. This method extends to other examples of convex geometries. We s...