Abstracts from this week's Nature.
Chris Burford
London
Multifractality in human heartbeat dynamics
PLAMEN CH. IVANOV, LUÍS A. NUNES AMARAL, ARY L. GOLDBERGER, SHLOMO HAVLIN, MICHAEL G. ROSENBLUM, ZBIGNIEW R. STRUZIK & H. EUGENE STANLEY
There is evidence that physiological signals under healthy conditions may have a fractal temporal structure. Here we investigate the possibility that time series generated by certain physiological control systems may be members of a special class of complex processes, termed multifractal, which require a large number of exponents to characterize their scaling properties. We report on evidence for multifractality in a biological dynamical system, the healthy human heartbeat, and show that the multifractal character and nonlinear properties of the healthy heart rate are encoded in the Fourier phases. We uncover a loss of multifractality for a life-threatening condition, congestive heart failure.
Fractal analysis of Pollock's drip paintings
RICHARD P. TAYLOR, ADAM P. MICOLICH & DAVID JONAS
Scientific objectivity proves to be an essential tool for determining the fundamental content of the abstract paintings produced by Jackson Pollock in the late 1940s. Pollock dripped paint from a can onto vast canvases rolled out across the floor of his barn. Although this unorthodox technique has been recognized as a crucial advancement in the evolution of modern art, the precise quality and significance of the patterns created are controversial. Here we describe an analysis of Pollock's patterns which shows, first, that they are fractal, reflecting the fingerprint of nature, and, second, that the fractal dimensions increased during Pollock's career.