High-precision test of isotropy of light propagation using actively rotated optical resonators

点击翻译按钮获取中文摘要

Local Lorentz Invariance (LLI) is a fundamental symmetry of nature that has until now experimentally been proven to be valid to a high degree. However, it is not known if LLI is strictly or only approximately valid. If a violation of LLI is found to exist, its detailed characterization could provide input for a fundamental theory of all forces. From the theoretical point of view, a violation of LLI is regarded as possible and models describing it have been proposed. For this reason there are worldwide efforts to perform more accurate experimental tests both on particles and on photons. Recently, we have performed the most precise (by a factor of 10) test of LLI for photons (Antonini et al., 2005), reaching the level (c/c < 6 ¿ 10-16.It is important to further improve this level by a few orders, since according to theoretical arguments, a possible level of LLI violation is given by the fundamental ratio Mw/Mplanck ( 1 ¿ 10-I7, where MW is the mass of the gauge bosons of the electroweak interaction. Our proposed experiment provides both the first and a strong test of Lorentz violation for photons (and non-spin contribution due to electrons) at this level.Within the proposed 3-year project we expect to:¿ improve the limits for a possible anisotropy of the velocity of light by a factor of 1000 to the level (c/c < 6 ¿ 10-19¿ measure 8 coefficients of the Standard Model extension theory with an accuracy between 100 and 1000 times higher than the currently best results, reaching a level of up to 2 ¿ 10-18.The experiment will be the first worldwide to explore LLI for photons at this level.The techniques we will develop will also make a significant contribution toward the development of ultrastable lasers suitable for next-generation optical atomic clocks.