Sagnac delay in the Kerr-dS spacetime: Implications for Mach’s principle R. Kh. Karimov, R. N. Izmailov, G. M. Garipova and K. K. Nandi Eur. Phys. J. Plus, 133 2 (2018) 44 Published online: 12 February 2018 DOI: 10.1140/epjp/i2018-11919-x