## 摘要

Gravity, and the puzzle regarding its energy, can be understood from a gauge theory perspective. Gravity, i.e., dynamical s-pacetime geometry, can be considered as a local gauge theory of the symmetry group of Minkowski spacetime: the Poincare group. The dynamical potentials of the Poincare gauge theory of gravity are the frame and the metric-compatible connection. The spacetime geometry has in general both curvature and torsion. Einstein's general relativity theory is a special case. Both local gauge freedom and energy are clarified via the Hamiltonian formulation. We have developed a covariant Hamiltonian formulation. The Hamiltonian boundary term gives covariant expressions for the quasi-local energy, momentum and angular momentum. A key feature is the necessity to choose on the boundary a non-dynamic reference. With a best matched reference one gets good quasi-local energy-momentum and angular momentum values.

原文 | ???core.languages.en_GB??? |
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主出版物標題 | Memorial Volume for Yi-shi Duan |

發行者 | World Scientific Publishing Co. Pte Ltd |

頁面 | 168-187 |

頁數 | 20 |

ISBN（電子） | 9789813237278 |

ISBN（列印） | 9789813237261 |

出版狀態 | 已出版 - 5 1月 2018 |