Objective Determination of Branching Angles in Fractals

Abstract
We propose an objective pattern recognition procedure to determine branching angles in 2-dimensional fractals. Recognition is performed by correlating the object with V-shaped identifiers. We define a quantitative criterion to prove the existence of characteristic branching angles in such figures. The whole procedure is tested on a mathematical (snowflake) fractal and then applied to a few physical examples. A neat characteristic angle is found in dendritic aggregates, in agreement with visual impression. However, the procedure does not find any dominant branching angle in basic Witten and Sander aggregates.