Possible altitudinal, latitudinal and directional dependence of
  relativistic Sagnac effect in Chern-Simons modified gravity
  Toward a test of parity violation in a gravity theory, possible effects of
Chern-Simons (CS) gravity on an interferometer have been recently discussed.
Continuing work initiated in an earlier publication [Okawara, Yamada and Asada,
Phys. Rev. Lett. 109, 231101 (2012)], we study possible altitudinal and
directional dependence of relativistic Sagnac effect in CS modified gravity. We
compare the CS effects on Sagnac interferometers with the general relativistic
Lense-Thirring (LT) effects. Numerical calculations show that the eastbound
Sagnac interferometer might be preferred for testing CS separately, because LT
effects on this interferometer cancel out. The size of the phase shift induced
in the CS model might have an oscillatory dependence also on the altitude of
the interferometer through the CS mass parameter $m_{CS}$. Therefore, the
international space station site as well as a ground-based experiment is also
discussed.
