Projective Cones for Sequential Dispersing Billiards

We construct Birkhoff cones for dispersing billiards, which are contracted by the action of transfer operator. This construction permits study statistical properties not only regular billiards but also sequential (the billiard changes at each collision in a prescribed manner), open dynamics exits some region or dies when hitting obstacle) and many other examples. In particular, we include applications to chaotic scattering random Lorentz gas.