I    Testing the General Theory of Relativity

In this section we present both old and recent observations and experiments which Newton's theory can not explain but which the GTR predicts to a great precision. Some of these experiments, such as the deflection of light at the solar limb, the time delay from Shapiro or the direct measurements of the effects of time using atomic clocks, can be calculated with our current resources to a good approximation of the expected results. For the perihelion of Mercury we can at least estimate the magnitude of the effect. For other experiments we must be satisfied that at least we understand that an effect is expected.