15 May 2023
Since the 70s, the Very Long Baseline Interferometry (VLBI) contributes to the precise monitoring of the Earth’s rotation and participates to the determination of reference frames. This technique consists in measuring the difference in the receiving times of radio waves’ planes emitted by distant sources, between two radio telescopes on Earth.
The precision of the measure is of the order of few picoseconds and the typical source is a distant quasar whose proper motion can be neglected due to its separation with the radio telescopes. Such a precision makes the measure dependent on spacetime symmetries.
The data processing of VLBI data in the SME framework revealed that the magnitude of the time-time SME coefficient of the pure gravity sector is lower than 10^-5. In other words, the VLBI data are coherent with predictions from general relativity.
Publications
- C. Le Poncin-Lafitte, A. Hees, et S. Lambert. Lorentz symmetry and very long baseline interferometry. PRD 94, 125030, 2016.