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  • Print publication year: 2018
  • Online publication date: September 2018

2 - The Einstein Equivalence Principle


We discuss the foundations of general relativity and all modern gravitational theories, based on the Einstein Equivalence Principle (EEP). We show that this principle is the basis for all metric theories of gravity including general relativity, in which gravity is a consequence of spacetime geometry. We review experimental test of the three pieces of EEP, the Weak Equivalence Principle, Local Lorentz Invariance and Local Position Invariance, and describe a number of general theoretical frameworks used to analyse EEP and its consequences.