论文标题
来自ALP域墙的Kilobyte Cosmic Birefringence
Kilobyte Cosmic Birefringence from ALP Domain Walls
论文作者
论文摘要
在早期的宇宙中可能形成无弦的ALP域壁。我们指出，这种ALP结构域壁导致宇宙微波背景（CMB）极化的各向同性和各向异性双折射，这反映了重组时域壁的空间构型。来自每个结构域的CMB光子的极化平面要么根本不旋转，要么以固定角度旋转。 For domain walls following the scaling solution, the cosmic birefringence of CMB is characterized by $2^{N}$, i.e. $N$-bit, of information with $N = {\cal O}(10^{3-4})$ being equal to the number of domains at the last scattering surface, and thus the name, $kilobyte~ cosmic~ birefringence$.各向同性双折射的大小与最近报道的值一致，而各向异性的差异是由最后一个散射表面的域的结构确定的。预测的宇宙双折射在广泛的ALP质量中是通用的，并耦合到光子。对这两个信号的检测将是无弦的ALP域壁的吸烟枪证据。
ALP domain walls without strings may be formed in the early Universe. We point out that such ALP domain walls lead to both isotropic and anisotropic birefringence of cosmic microwave background (CMB) polarization, which reflects spatial configuration of the domain walls at the recombination. The polarization plane of the CMB photon coming from each domain is either not rotated at all or rotated by a fixed angle. For domain walls following the scaling solution, the cosmic birefringence of CMB is characterized by $2^{N}$, i.e. $N$-bit, of information with $N = {\cal O}(10^{3-4})$ being equal to the number of domains at the last scattering surface, and thus the name, $kilobyte~ cosmic~ birefringence$. The magnitude of the isotropic birefringence is consistent with the recently reported value, while the anisotropic one is determined by the structure of domains at the last scattering surface. The predicted cosmic birefringence is universal over a wide range of the ALP mass and coupling to photons. The detection of both signals will be a smoking-gun evidence for the ALP domain walls without strings.
