  We study phase slips in one-dimensional topological superconducting wires.
These wires have been proposed as building blocks for topologically protected
qubits in which the quantum information is distributed over the length of the
device and thus is immune to local sources of decoherence. However, phase-slips
are non-local events that can result in decoherence. Phase slips in topological
superconductors are peculiar for the reason that they occur in multiples of
4\pi\ (instead of 2\pi\ in conventional superconductors). We re-establish this
fact via a beautiful analogy to the particle physics concept of dynamic
symmetry breaking by explicitly finding a "hidden" zero mode in the fermion
spectrum computed in the background of a 2\pi\ phase-slip. Armed with the
understanding of phase-slips in topological superconductors, we propose a
simple experimental setup with which the predictions can be tested by
monitoring tunneling rate of a superconducting flux quantum through a
topological superconducting wire.
