I am writing an essay on the Berry Keating article proposing to use the $\mathcal{H}=xp$ hamiltonian to get a correspondence between the nontrivial riemann zeros and the eigenvalues of an Hermitian operator. Now classically, the time evolution of the system as follows from the Hamilton equations is:
$$ x(t)=x(0)e^t $$ $$p(t) = p(0)e^{-t} $$
It seems as if the particle is accelerating (since $\frac{dx}{dt}$ clearly increases), while $p$ obviously decreases. Moreover I do not immediately see how this system is chaotic, although clearly the distance as a result of different initial conditions between particles increases over time. Could you please shed some light on this?