理物理的方法等效原理到宇宙-NTU.ppt

COSMIC POLARIZATION ROTATION COSMOLOGICAL MODELS AND Detectability of Primordial G-Waves Wei-Tou Ni Center for Gravitation and Cosmology, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing, CHINANational Astronomical Observatories, Chinese Academy of Sciences, Beijing, CHINA  CMB Polarization Observation In 2002, DASI microwave interferometer observed the polarization of the cosmic background. With the pseudoscalar-photon interaction , the polarization anisotropy is shifted relative to the temperature anisotropy. In 2003, WMAP found that the polarization and temperature are correlated to 10σ. This gives a constraint of 10-1 rad or 6 degrees of the cosmic polarization rotation angleΔφ. CMB Polarization Observation In 2005, the DASI results were extended (Leitch et al.) and observed by CBI (Readhead et al.) and CAPMAP (Barkats et al.) In 2006, BOOMERANG CMB Polarization DASI, CBI, and BOOMERANG detections of Temperature-polarization cross correllation Planck Surveyor will be launched next year with better polarization-temperature measurement and will give a sensitivity to cosmic polarization rotation Δφ of 10-2-10-3. WMAP 3 year Polarization Maps Pseudo-scalars: Pseudoscalar-Photon Coupling ≈ ξφ,μ AνF~μν  ≈ ξ (1/2)φ FμνF~μν(Mod Divergence) Change of Polarization due to Cosmic Propagation The effect of φ in (2) is to change the phase of two different circular polarizations of electromagnetic-wave propagation in gravitation field and gives polarization rotation for linearly polarized light.[6-8] Polarization observations of radio galaxies put a limit of Δφ ≤ 1 over cosmological distance.[9-14] Further observations to test and measure Δφ to 10-6 is promising. The natural coupling strength φ is of order 1. However, the isotropy of our observable universe to 10-5 may leads to a change (ξ)Δφ of φ over cosmological distance scale 10-5 smaller. Hence, observations to test and measure Δφ to 10-6 are needed. Pseudoscalar-Photon Interaction