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Testing General Relativity with Gravitational Lensing. -Rhondale Tso -Dr. Quentin Bailey (Embry-Riddle Aeronautical University). NASA Space Grant Presentation. Basics of General Relativity. Einstein Tensor. Energy-Momentum Tensor. *Curvature is caused by the Energy and Momentum.
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Testing General Relativity with Gravitational Lensing -Rhondale Tso -Dr. Quentin Bailey (Embry-Riddle Aeronautical University) NASA Space Grant Presentation
Basics of General Relativity Einstein Tensor Energy-Momentum Tensor *Curvature is caused by the Energy and Momentum. *Matter changes the properties of spacetime.
Basics of General Relativity Light-ray *Gravity corresponds to changes in the properties of space and time. *Alters the straightest possible, or shortest, paths that objects naturally follow (including light!!).
Incompatible with Quantum Mechanics (so far). • Assumes local Lorentz symmetry (locally the laws of physics obey special relativity). • Recent literature points to the possibility that Local Lorentz symmetry might be slightly broken. • Standard Model Extension (SME) framework describes this scenario general using modern"field theory" What’s wrong with General Relativity?
SME experiments testing Lorentz symmetry to date: • meson oscillations (BABAR, BELLE, DELPHI, FOCUS, KTeV, OPAL, …) • neutrino oscillations (MiniBooNE, LSND, Minos, Super K,… ) • muon tests (Hughes, BNL g-2) Yale, … • spin-polarized torsion pendulum tests (Adelberger, Hou, …) U. of Washington • tests with resonant cavities (Lipa, Mueller, Peters, Schiller, Wolf, …) • Stanford, Institut fur Physik, Univ. West. Aust. • clock-comparison tests (Hunter, Walsworth, Wolf, …) Harvard-Smithsonian • Penning-trap tests (Dehmelt, Gabrielse, …) U. of Washington • Lunar laser ranging (Battat, Stubbs, Chandler) Harvard • Atom interferometric gravimeters (Chu, Mueller, …) Stanford • cosmological birefringence (Carroll, Jackiw, Mewes, Kostelecky) MIT, IU • pulsar timing (Altschul) South Carolina • synchrotron radiation (Altschul) South Carolina • Cosmic Microwave Background (Mewes, Kostelecky) Marquette U., IU
Due to curvature of spacetime light gets bent around massive objects; General Relativity prediction: Standard Model Extension prediction: Introduce “s-bar” coefficients. *SME prediction can be applied to the Lensing Equation. *S-bar coefficients tell whether Lorentz Violations affects gravity, if the S-bar=0, then no Lorentz Violations.
Results and Upcoming tests. • Application to Light Bending is still underway. Future tests to detect deviations include: • Global Astrometric Interferometer for Astrophysics (GAIA), from the ESA. • Very Long Baseline Interferometer (VLBI).