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TheMössbauer effect and quasi-elastic neutron scattering(QENS) from hydrated proteins yield sharp elastic lines that are accompaniedby broad wings. Conventionally, the elastic line and the broad wingsare treated as separate phenomena. We show that there is no separation;the entire spectrum consists of Lorentzians with the natural linewidth. In protein crystals, the shifts of the individual lines fromthe elastic center above about 150 K are caused by beta fluctuationsin the hydration shell. Vibrations cause shifts in the entire temperaturerange but are best seen below about 150 K. We construct a microscopicmodel for the dynamics that is based on a random walk of the proteinsin their free-energy landscape. The model yields approximate valuesfor the steps in the energy landscape. Remarkably, the quantum electrodynamicconcept of gamma rays is needed to justify the model. [ABSTRACT FROM AUTHOR]