SPIRAL WAVE DYNAMICS

We analyse time series of meandering spiral waves in a two-dimensional model of excitable tissue. Time series of the spiral tip studied are quasiperiodic and erratic. In the case of erratic motion an intrinsic non-stationarity of the tip position is present due to the possibility of arbitrary large excursions. The correlation dimension D-2 and corr elation entropy K-2 are then not well defined. However, low-dimensiona l behaviour is found in the spiral tip velocity for the erratic series . Non-stationarity of the tip position can be explained from chaotic b ehaviour of the tip velocity.