Somewhere on the sun, light does not shine out
نویسنده
چکیده
Work during 1870-1970 had shown that spherically symmetric electromagnetic, gravitational, or massless-neutrino energy flows were impossible. These impossibilities were thought by their discoverers to be isolated results dependent on the field equations obeyed by these kinds of energy. But we now show that they are consequences of extremely general and simple topological impossibilities, and have little or nothing to do with the field equations. Consequently we get more general impossibility results from shorter and simpler proofs. We also get a complete classification of the allowed topologies of electromagnetic, gravitational, or neutrino wavefronts – only planes, infinite cylinders, and tori are allowed.
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