Harry Varvoglis

Research Interests

Non-linear Dynamical Systems: phase space structure and onset of stochaticity

• In collaboration with Chistos Vozikis and Basil Barbanis we study the topological structure of phase space in model perturbed integrable Hamiltonians with three degrees of freedom. Main results: (a) The phase space has fractal properies and (b) the contour of the Local (or Short-time) Liapunov Numbers are correlated with the network of the Farey tree lines.
• In collaboration with Christos Vozikis ans Menios Tsiganis we study the onset of stochastic behaviour in perturbed integrable Hamiltonians (model as well as representing actual dynamical systems). We have proposed a new criterion for the early detection of chaotic orbits based on the power spectrum of geodesic divergences

Asteroidal dynamics

• In collaboration with Menios Tsiganis, Anastasios Anastasiadis (Athens) and John Hadjidemetriou we study transort in the asteroidal belt as a diffusion process.

Three-body Coulomb problem

• In collaboration with Konstantinos Katsonis (Paris) we study the fractality in the initial conditions space in the problem of ion-atom collisions relevant to the Classical Trajectory Monte Carlo (CTMC) method in the calculation of ionisation and charge-transfer effective cross-sections

Two fixed centers problem

• In collaboration with Christos Vozikis and Karl Wodnar (Vienna) we study the properties of trajectories in the "classica" two-fixed-centers problem.

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