Modeling transverse relative locality

Abstract: We investigate some aspects of relativistic classical theories with "relative locality", in which pairs of events established to be coincident by nearby observers may be described as non-coincident by distant observers. While previous studies focused mainly on the case of longitudinal relative locality, where the effect occurs along the direction connecting the distant observer to the events, we here focus on transverse relative locality, in which instead the effect is found in a direction orthogonal to the one connecting the distant observer to the events. Our findings suggest that, at least for theories of free particles such as the one in arXiv:1006.2126, transverse relative locality is as significant as longitudinal relative locality both conceptually and quantitatively. And we observe that "dual gravity lensing", first discussed in arXiv:1103.5626, can be viewed as one of two components of transverse relative locality. We also speculate about a type of spacetime noncommutativity for which transverse relative locality could be particularly significant.