Class | Invariance | Conserved Quantity |
---|---|---|

Proper
orthochronous Lorentz symmetry |
translation in space | linear momentum |

rotation in space | angular momentum | |

translation in time | energy | |

Discrete symmetry | P, coordinates' inversion | spatial parity |

C, charge conjugation | charge parity | |

T, time reversal | time parity | |

CPT | product of parities | |

Internal symmetry | EM (U1) gauge transformation | electric charge |

G parity | ||

isospin | ||

hypercharge | ||

lepton generation number | ||

baryon number | ||

quark color | ||

quark flavor |

http://www.shef.ac.uk/uni/academic/N-Q/phys/teaching/phy304/invariance.html

Linear and angular momenta, mass-energy, and electric charge are strongly conserved ("black holes have no hair"). CPT, baryon number, lepton generation number, and quark color are locally conserved. Processes that violate parity conservation can violate the remainder. Parity/chirality is a powerful inquiry.

Geometric spacetime is incompatible with quantum mechanics that dominates physics as virtual particle exchanges. General Relativity demands symmetry under all smooth coordinate transformations, resisting quantization. (General Relativity may be vulnerable to parity challenges as are weakly conserved quantities. Nobody has looked.) Relativity is accurate to eleven decimal places in the Global Positioning Satellite system[10]. Any relativistic classical field theory can be at best the classical limit of a relativistic quantum field theory. There are no known empirical exceptions to the Equivalence Principle. Good people continue to seek one by watching things fall:

Year | Investigator | Sensitivity | Method |
---|---|---|---|

500? | Philoponus[11] | "small" | Drop Tower |

1590? | Galileo[5] | 2x10^{-2} |
Pendulum, Drop Tower |

1686 | Newton[6] | 10^{-3} |
Pendulum |

1832 | Bessel[12] | 2x10^{-5} |
Pendulum |

1910 | Southerns[13] | 5x10^{-6} |
Pendulum |

1923 | Potter[14] | 3x10^{-6} |
Pendulum |

1918 | Zeeman[15] | 3x10^{-8} |
Torsion Balance |

1922 | Eötvös[16] | 5x10^{-9} |
Torsion Balance |

1935 | Renner[17] | 2x10^{-9} |
Torsion Balance |

1964 | Dicke,Roll,Krotkov[18] | 3x10^{-11} |
Torsion Balance |

1972 | Braginsky,Panov[19] | 10^{-12} |
Torsion Balance |

1976 | Shapiro, et al.[20] | 10^{-12} |
Lunar Laser Ranging |

1981 | Keiser,Faller[21] | 4x10^{-11} |
Fluid Support |

1987 | Niebauer, et al.[22] | 10^{-10} |
Drop Tower |

1989 | Heckel, et al.[23] | 10^{-11} |
Torsion Balance |

1990 | Adelberger, et al.[24] | 10^{-12} |
Torsion Balance |

1999 | Adelberger, et al.[25] | 10^{-13} |
Torsion Balance |

2005? | MiniSTEP[26] | 10^{-18} |
Earth Orbit |

http://einstein.stanford.edu/STEP/information/data/gravityhist2.html