  The quantum chaos is related to a Gaussian random matrix model, which shows a
dip-ramp-plateau behavior in the spectral form factor for the large size $N$.
The spectral form factor of time dependent Gaussian random matrix model shows
also dip-ramp-plateau behavior with a rounding behavior instead of a kink near
Heisenberg time. This model is converted to two matrix model, made of $M_1$ and
$M_2$. The numerical evaluation for finite $N$ and analytic expression in the
large $N$ are compared for the spectral form factor.
