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arXiv · 0710.3325

Testing CPT Symmetry with CMB Measurements

Jun-Qing Xia·Hong Li·Xiulian Wang·Xinmin Zhang
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Abstract

In this paper we study the possibility of testing \emph{CPT} symmetry with Cosmic Microwave Background (CMB) measurements. Working with an effective lagrangian of the photon with \emph{CPT} violation ${\cal L} \sim p_μA_ν\tilde F^{μν}$ which causes the polarization vectors of the propagating CMB photons rotated, we determine the rotation angle $Δα$ using the BOOMERanG 2003 and the WMAP3 angular power spectra. In this analysis we have included the newly released $TC$ and $GC$ ($l<450$) information of WMAP3 and found $Δα=-6.2\pm3.8$ deg at $1σ$ confidence level. This result increases slightly the significance for the \emph{CPT} violation obtained in our previous paper (Feng \emph{et al.}, 2006) $Δα=-6.0 \pm 4.0$ deg (1$σ$). Furthermore we examine the constraint on the rotation angle with the simulated Planck data. Our results show that the Planck will be sensitive to $Δα$ at the level of 0.057 deg and able to test the \emph{CPT} symmetry with a higher precision.

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Jun-Qing Xia, Hong Li, Xiulian Wang, Xinmin Zhang. 2008-02-27. Testing CPT Symmetry with CMB Measurements. https://doi.org/10.1051/0004-6361%3A200809410

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