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Gravitation: Theories & Experiments. Clifford M. Will and Gilles Esposito-Farèse. Part 1. Clifford Will James S. McDonnell Professor of Physics McDonnell Center for the Space Sciences Department of Physics Washington University, St. Louis USA http://wugrav.wustl.edu/people/CMW
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Gravitation: Theories & Experiments Clifford M. Will and Gilles Esposito-Farèse Part 1 Clifford Will James S. McDonnell Professor of Physics McDonnell Center for the Space Sciences Department of Physics Washington University, St. Louis USA http://wugrav.wustl.edu/people/CMW cmw@wuphys.wustl.edu
Outline of the Lectures Lecture 1: The Einstein Equivalence Principle Lecture 2: Post-Newtonian Limit of GR Lecture 3: The Parametrized Post-Newtonian Framework Lecture 4: Tests of the PPN Parameters
Outline of the Lectures • Lecture 1: The Einstein Equivalence Principle • Review of dynamics in special relativity • The weak equivalence principle • The Einstein equivalence principle • Tests of EEP • Tests of WEP • Tests of local Lorentz invariance • Tests of local position invariance • Metric theories of gravity • Non metric theories of gravity • Physics in curved spacetime • Lecture 2: Post-Newtonian Limit of GR • Lecture 3: The Parametrized Post-Newtonian Framework • Lecture 4: Tests of the PPN Parameters
The Weak Equivalence Principle (WEP) 400 CE Ioannes Philiponus: “…let fall from the same height two weights of which one is many times as heavy as the other …. the difference in time is a very small one” 1553 Giambattista Benedetti proposed equality 1586 Simon Stevin experiments 1589-92 Galileo Galilei Leaning Tower of Pisa? 1670-87 Newton pendulum experiments 1889, 1908 Baron R. von Eötvös torsion balance experiments (10-9) 1990s UW (Eöt-Wash) 10-13 Bodies fall in a gravitational field with an accelerationthat is independent of mass, composition or internal structure
The Einstein Equivalence Principle (EEP) • Test bodies fall with the same acceleration • Weak Equivalence Principle (WEP) • In a local freely falling frame, physics (non-gravitational) is independent of frame’s velocity • Local Lorentz Invariance (LLI) • In a local freely falling frame, physics (non-gravitational) is independent of frame’s location • Local Position Invariance (LPI)
Tests of the Weak Equivalence Principle APOLLO (LLR) 10-13 Microscope 10-15(2008) STEP 10-18 (?)
Lorentz non-invariant EM action Under a Lorentz transformation, eg
Tests of Local Position Invariance ACES(2010) 10-6
Metric Theories of Gravity • Spacetime is endowed with a metric gmn • The world lines of test bodies are geodesics of that metric • In a local freely falling frame (local Lorentz, or inertial frame), the non-gravitational laws of physics are those from special relativity • “universal coupling principle”
The Them Framework T, H, e, m are functions of an external static spherical potential U(r) Metric theory action iff with
Standard Model Extension (SME) Kostelecky et al • Clock comparisons • Clocks vs cavities • Time of flight of high energy photons • Birefringence in vacuum • Neutrino oscillations • Threshold effects in particle physics If the universe is fundamentally isotropic D. Mattingly, Living Reviews in Relativity 8, 2005-5
Outline of the Lectures Lecture 1: The Einstein Equivalence Principle Lecture 2: Post-Newtonian Limit of GR Lecture 3: The Parametrized Post-Newtonian Framework Lecture 4: Tests of the PPN Parameters