AN INTERFACE OBTAINED BY COLLISION OF 2 INDEPENDENT ROUGH SURFACES - INVASION BY BURNING OF PAPER

The growing surface at a fire front has the property of self-affinity. We start fires from two opposite edges of rectangular paper and ob ta in two independent rough surfaces with roughness exponent alpha = 0.73 and growth exponent beta = 0.47. The two independent fronts later col lide in the central region of the paper to form an interface with roug hness exponent alpha' = 0.67 and growth exponent beta' = 0.22.