Running of Newton's Constant and Quantum Gravitational Effects
David Reeb
备注：
11 pages, 5 figures, latex; contribution to the proceedings of the 46th course of the International School of Subnuclear Physics held in Erice, Sicily/Italy, August 29 - September 7, 2008
发表信息：
Proceedings of the International School of Subnuclear Physics, 46th course: "Predicted and totally unexpected in the energy frontier opened by LHC" (Ed. A. Zichichi), World Scientific (2011)
Newton's gravitational constant is shown to be a running coupling constant, much like the familiar running gauge couplings of the Standard Model. This implies that, in models with appropriate particle content, the true Planck scale, i.e. the scale at which quantum gravity effects become important, can have a value different from 10^19 GeV, which would be expected from naive dimensional analysis. Then, two scenarios involving this running effect are presented. The first one is a model which employs huge particle content to realize quantum gravity at the TeV scale in 4 dimensions, thereby solving the hierarchy problem of the Standard Model. Secondly, effects of the running of Newton's constant in grand unified theories are examined and shown to introduce new significant uncertainties in their predictions, but possibly also to provide better gauge coupling unification results in some cases.
Instituto de Física Teórica UAM/CSIC（马德里自治大学/西班牙国家研究委员会理论物理研究所）；Leinweber Institute for Theoretical Physics at Stanford, Department of Physics, Stanford University（斯坦福大学莱因韦伯理论物理研究所物理系）
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