- #1

spaghetti3451

- 1,344

- 34

## Homework Statement

Consider the following differential equation

$$\frac{\partial^{2}\phi}{\partial t^{2}}-\nabla^{2}\phi = \phi(a-b\phi^{2}), \qquad a>0.$$

I would like to prove that $\phi=0$ is an unstable solution of this equation.

## Homework Equations

## The Attempt at a Solution

Do you suggest a numerical approach?

Can this not be done analytically?