The Shrinking ``Fermi Arc'' in Cuprates

The angle-resolved photoemission spectroscopy (ARPES) on cuprates in the pseudogap region reveal an extraordinary topological transition in which the ground state changes from one with a usual Fermi surface to one with four Fermi points. We argue that such a state is not possible without some symmetry breaking which allows interference between one-particle basis states which is normally forbidden. We also show that the experimental results are quantitatively given without any free parameters by a theory and discuss the implications of the results.