Home | Contact | Sitemap | 中文 | CAS
Search: 
Home │  About Us │  Research │  People │  International Cooperation │  Education & Training │  Papers
  Seminar
Conference
Forum on FS
Colloquium
Seminar
Lunch Seminar
Coffee Time
Advanced Course
KITPC Activities
Other activities
  Location: Home >  Research Activities >  Seminar
On Lorentz violation in Horava-Lifshitz type theories
2011-06-16     Text Size:  A
Institute of Theoretical Physics
Chinese Academy of Sciences
学术报告
Title
题目
On Lorentz violation in Horava-Lifshitz type theories
Speaker
报告人
Dr. Yanwen Shang
Perimeter Institute, Canada
Date
日期
2011-06-16 PM 14:30 Thursday
Venue
地点
Conference Hall 322, ITP/理论物理所322报告厅
Abstract
摘要

Lorentz symmetry is a fundamental symmetry of Nature, and if at smallest scale, the symmetry is broken, as many suggestions to the theories of quantum gravity would "naturally predict", there is a long-standing puzzle how one can acquire Lorentz symmetry as an emergent symmetry at extremely high precision at low energy. We show that coupling the Standard Model to a Lorentz symmetry violating sector may co-exist with viable phenomenology, provided that the interaction between the two is mediated by higher-dimensional operators. In particular, if the new sector breaks Lorentz symmetry by acquiring anisotropic scaling behavior above a "Horava-Lifshitz" energy scale $Lambda_L$ and couples to the Standard Model through interactions suppressed by the Planck mass $M_p$, the transmission of the Lorentz violation into the Standard Model is protected by the ratio $Lambda_L^2/M_p^2$. A wide scale separation, $Lambda_L<<M_p$, can then make Lorentz-violating terms in the Standard Model sector within experimental bounds without fine-tuning. We first illustrate our point by a toy example and then explain that the proposal unfortunately does face some difficulty due to the existence of instantaneously propagating non-Lifshitz modes in gravity.

  Appendix:
       Address: No. 55 Zhong Guan Cun East Road, Haidian District, Beijing 100190, P. R. China
Copyright ? Institute of Theoretical Physics, Chinese Academy of Sciences, All Rights Reserved