**Special Relativity**Einstein's Special Theory of Relativity which was popularized in 1905, replacing Newton opinion about space and time, and include electromagnetism as written by Maxwell's equations. Why is this theory called "special" because he applies the principle of relativity in the case of "certain" or "special" from the inertial reference frame in flat space-time, where the effects of gravity are negligible. Eleven years later (1916) Einstein published his general relativity theory insert effects.

Many of the predictions of general relativity that is different from classical physics predictions, especially predictions about the passage of time, the geometry of space, the motion of objects in free fall, and the propagation of light. Examples of these differences include gravitational time dilation, shearing gravitational red light, and the gravitational time delay. Predictions of general relativity have been confirmed in all experiments and observations of physics. The existence of these waves have been measured indirectly, and there are also some attempt was made to measure directly. General relativity is also the basis for the cosmological model of the universe is constantly evolving.

This theory is an explanation of the latest gravity in modern physics. He unites Einstein's theory earlier, special relativity, the law of Newtonian gravity. This is done by looking at the gravity not as a force, but rather as a manifestation of the curvature of space and time. Primarily, the curvature of space-time is directly related to the four momentum (mass energy and linear momentum) of whatever matter and radiation are present. This relationship is described by the Einstein field equations.

Einstein's theory has important astrophysical implications, because it predicts the existence of black holes are areas where space and time are distorted in such a way no one else, even light, can escape it. There is evidence that black holes and other types of black holes other larger responsible for the intense radiation emitted by astronomical objects, such as active galactic nuclei and mikcro quasar. Curved light by gravity can lead to the phenomenon of gravitational lensing. Unfortunately, Western scientists such as Einstein predecessor Galileo, Descartes and Newton regard all phenomena as something absolute.

*General Relativity*Could Albert Einstein made mistakes in the theories that have drawn up? To answer this question is not easy. Since almost all of which Einstein proposed the theory has been proven through experiments. But there is one theory that is still not yet fully tested: the theory of general relativity.

For that a satellite called Gravity Probe (GP) B was launched on Monday, April 19th, 2004 at 10:01 am Pacific time from Vandenberg Air Force Base, Southern California. The project has been delayed all these years miliun worth 700 dollars. This satellite was launched with one goal

The main purpose of this experiment was to test the truth of the premise of the main fields of space and time that Einstein proposed as the basis of the theory of general relativity. Satellite GP B consisting of the telescope and the gyroscope system is going round the earth from the north pole to the south with an altitude of 640 km for up to two years. Satellites with highly sophisticated equipment is expected to detect the effect of the geometry of space and time fields in the vicinity of the influence of the mass of the earth

This paper will consist of two parts. The first section will familiarize the reader with Einstein's theory of general relativity, which predicted a natural phenomenon as a result of this theory and experiments that have been performed as a confirmation of earlier predictions. The second part discusses further experiments are being carried out in GP project B to prove the claim about the fields of space and time.

After ten years of struggling with both of these issues, in 1916 Einstein came up with a new theory of gravity based on the perception of time and space completely different from the way Newton. If Newton saw space as empty space, Einstein considered space is made of woven fields of space and time. This new theory of gravity known as general relativity.

Field of time and space is 4-dimensional field, derived from the three-dimensional space and one dimension of time comes. The form of a webbing of space and time is greatly influenced by the distribution of mass or energy inside the 4-dimensional field. Celestial bodies like the sun will dent this field. Curve effect can be imagined as a rubber cup mattress surface caused by a bowling ball on it. As a concern, two-dimensional picture of the curve of the mattress is only to simplify the description of 4-dimensional curve that hard to imagine. This phenomenon is known as the warped space-time or space-time warp.