Dear kallog,

Two way time transfer experiment tells us that in the ground reference system we can detect Sagnac effect due to the Earth's rotation. Electromagnetic waves back and forth between China and Japan, the difference in time of about 90ns.
Why can not we detect Sagnac effect due to the Earth's revolution? It should be about 6000ns. Some people tried to explain that it should not be detected, but this means that two beams of light can return to point O at the same time after gyratinga circuit.
Please seriously consider this issue. Thanks!

Best Regards
Xinwei Huang