Impact of non-random vibrations in Mössbauer rotor experiments testing time dilation

¹ Jerusalem College of Technology - P.O.B. 16031 Jerusalem 91160, Israel
² Racah Institute of Physics, Hebrew University - Jerusalem 91904, Israel
³ Deutsches Elektronen-Synchrotron - Notkestr. 85, D-22607 Hamburg, Germany
⁴ Dep. Physik, Universität Paderborn - Warburger Str. 100, D-33098 Paderborn, Germany
⁵ Ben-Gurion University of the Negev - P.O.B 653, Beer-Sheva 8410501, Israel
⁶ European Synchrotron Radiation Facility - BP 220, F-38043 Grenoble, France

Received: 14 March 2016
Accepted: 17 June 2016

Abstract

All experiments testing time dilation by measuring the spectral shift of a rotating Mössbauer absorber assume that vibrations do not affect the spectral shift because of their purely random nature and claim that the observed shift is due to time dilation only. Our recent experiment using the Synchrotron Mössbauer Source at ESRF revealed, however, a shift due to the non-random periodic vibration patterns caused by the rotor/bearing system. These patterns fit the predictions of the Jeffcott model for such a system with non-zero eccentricity. We have calculated this shift due to the non-random vibrations and the resulting relative shift between two states when the acceleration of the absorber is anti-parallel and parallel to the source. This relative shift exhibits the same behavior as the observed relative shift. Hence, the effect of the spectral shift due to vibrations cannot be ignored in any Mössbauer rotor experiments for testing time dilation. Recommendations for improvement of future rotor experiments testing time dilation are presented.