Neutron spin optics: A thought experiment with applications

We introduce the concept of neutron spin optics - using the analogy between the phase of the Larmor precession in a constant magnetic field and that of an optical wave field to produce well known diffraction and interference effects in a new medium - and show how this adds a new perspective to the discussion of the two slit interference problem opening up the possibility of a description in terms of classical ''hidden variables''. We then show how this may have applications in the extension of elastic neutron scattering to regions of momentum transfer inaccessible to existing techniques.