49 citations · 149 across the 13 of their papers we have counts for
15 papers
Universal supercritical behavior for some skew-product maps
Hans Koch
We consider skew-product maps over circle rotations (mod 1) with factors that take values in SL(2,R) In numerical experiments with the inverse golden mean, Fibon…
Asymptotic scaling and universality for skew products with factors in SL(2,R)
Hans Koch
We consider skew-product maps over circle rotations (mod 1) with factors that take values in SL(2,R). This includes maps of almost Mathieu type. In numerical experim…
A Hopf bifurcation in the planar Navier-Stokes equations
Gianni Arioli, Hans Koch
We consider the Navier-Stokes equation for an incompressible viscous fluid on a square, satisfying Navier boundary conditions and being subjected to a time-independent force. As th…
On trigonometric skew-products over irrational circle-rotations
Hans Koch
We describe some asymptotic properties of trigonometric skew-product maps over irrational rotations of the circle. The limits are controlled using renormalization. The maps conside…
Renormalization and universality of the Hofstadter spectrum
Hans Koch, Sasha Kocic
We consider a renormalization transformation for skew-product maps of the type that arise in a spectral analysis of the Hofstadter Hamiltonian. Periodic orbits of determine…
Golden mean renormalization for the almost Mathieu operator and related skew products
Hans Koch
Considering SL(2,R) skew-product maps over circle rotations, we prove that a renormalization transformation associated with the golden mean alpha has a nontrivial periodic orbit of…