Physics Letters A
A fiber optic conveyor has been developed for investigating the travel-time difference between two counter-propagating light beams in uniformly moving fiber. Our finding is that there is a travel-time difference Δt = 2vΔl/c2 in a fiber segment of length Δl moving with the source and detector at a speed v, whether the segment is moving uniformly or circularly.
Zheng, Yi; Yao, Aiping; Wang, Ruyong; and Langley, Dean, "Modified Sagnac experiment for measuring travel-time difference between counter-propagating light beams in a uniformly moving fiber" (2003). Electrical and Computer Engineering Faculty Publications. 3.