Fractals and multifractals: Applications in physics

Critical fluctuations, growth or disorder can produce fractal structures which have unusual physical properties due to their scale invariance. Particularly interesting are the so called multifractals measures that can exist on these fractals. We will introduce the concept of multifractals and the most common way to formalize them via the function f(α). We will present three situations in which multifractality appears: percolation, growth phenomena and fracture.