Barut, A. O. and J. Nagel.
Text: "Interpretation of space-like solutions of infinite-component wave equations and Grodsky-Streator 'No-Go' theorem" "No-Go" theorem which admits only time-like solutions should also include space-like solutions of infinite-component wave equations Journal of Physics A: Mathematical and General. 10(7), July, 1977. p. 1223-1242.
See Also: foundations of physics, quantum electrodynamics.
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