5. Aggregation models

Many fractal objects are structures formed by the aggregation of small particles. Sometimes, we have an intuition of the reason why such aggregation leads to the formation of fractals, as in the case of cluster processes, which are essentially hierarchical, but for other processes, the appearance of fractality still remains a mystery and is only a numerical and/or experimental observation.

We will review some of the most important typical processes in this field of Physics