The Nonlocality of Topological Quantum Phases

Document Type


Publication Date



Are the electromagnetic scalar and vector potentials dispensable? Lev Vaidman has suggested that local interactions of gauge-invariant quantities, e.g. magnetic torques, suffice for the description of all quantum electromagnetic phenomena. We analyze a selection of thought experiments that challenge this suggestion. All of them have explanations in terms of local interactions of gauge-dependent quantities; in addition, some have explanations in terms of nonlocal interactions of gauge-invariant quantities. We claim, however, that two of our examples have no gauge-invariant explanation and that electromagnetic potentials are, in general, truly indispensable.


This is the pre-print of an article that may be published at a later date. This version has not yet undergone peer review and may differ from the final, published version.


The authors