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New dissipated energies for the thin fluid film equation
The thin fluid film evolution $h_t = -(h^n h_{x x x})_x$ is known to
conserve the fluid volume $\int h dx$ and to dissipate the
"energies" $\int h^{1.5-n} dx$ and $\int h_x^2 dx$.
We extend this last result by showing the energy $\int h^p h_x^2
dx$ is dissipated for some values of $p < 0$, when
$\frac{1}{2} < n < 3$. For example when $n=1$, the Hele-Shaw
equation $h_t = -(h h_{x x x})_x$ dissipates $\int h^{-1/2} h_x^2 dx$.