Masahito Ohta

Strong instability of standing waves for the nonlinear klein-gordon equation and the klein-gordon-zakharov system

The orbital instability of ground state standing waves

Bifurcation from Semitrivial Standing Waves and Ground States for a System of Nonlinear Schrödinger Equations

e^{iomega t}phi_{omega}(x)

STABILITY OF SOLITARY WAVES FOR THE OSTROVSKY EQUATION

for the nonlinear Klein–Gordon equation has been known in the domain of all frequencies ω for the supercritical case and for frequencies strictly less than a critical frequency

On the Global Behavior of Classical Solutions to Coupled Systems of Semilinear Wave Equations

omega_c

Nonlinear Schrödinger equation with a point defect

in the subcritical case. We prove the strong instability of ground state standing waves for the entire domain above. For the case when the frequency is equal to the critical frequency

Stability of solitary waves for derivative nonlinear Schrödinger equation

omega_c

Stability of solitary waves for a system of nonlinear Schrödinger equations with three wave interaction

we prove strong instability for all radially symmetric standing waves

Stability of standing waves for nonlinear Schrödinger equations with potentials

e^{iomega_c t}varphi(x)

Strong instability of standing waves for nonlinear Klein-Gordon equations

. We prove similar strong instability results for the Klein–Gordon–Zakharov system.

Strong instability of solitary waves for nonlinear Klein–Gordon equations and generalized Boussinesq equations

We consider a system of nonlinear Schrodinger equations related to the Raman amplification in a plasma. We study the orbital stability and instability of standing waves bifurcating from the semitrivial standing wave of the system. The stability and instability of the semitrivial standing wave at the bifurcation point are also studied. Moreover, we determine the set of the ground states completely.