The paper describes the
structure of finite dimensional representations of BT, the crossed-product algebra of
a classical dynamical system (αT, ℤ,C(X)) where T is a homeomorphism on a
compact space X. The results are used to describe the topology of Primn(BT) and to
partially classify the hyperbolic crossed-product algebras over the torus.
One of the main results is that the number of orbits of any fixed length
with respect to T is an invariant of BT. A consequence of that is that the
entropy of T is an invariant of BT, for T a hyperbolic automorphism on the
m-torus.