Frame dragging and Lense-Thirring effect (Q1768442)

The author describes some phenomena due to spin and mass-energy currents on clocks and photons. In particular the delay in the travel time of photons due to the spin of a body is obtained both inside a rotating shell and outside a rotating body. The author reviews the 1995-2001 measurements of the gravitomagnetic field of Earth and Lense-Thirring effect obtained by analyzing the orbits of the two laser-ranged satellites LAGEOS (LAser GEOdynamics Satellite) and LAGEOS II. The latest measurement of the Lense-Thirring effect, obtained in 2003 with the two LAGEOS satellites over more than 10 years are reported. The result fully confirms and improves the previous measurements of the Earth frame-dragging. The main result is that the Lense-Thirring effect exists and its experimental value is within \(\sim 20 \%\) of what is predicted by Einstein's theory of General Relativity.