Renormalization in gravitational leptogenesis with pseudo-scalar-tensor coupling
Renormalization in gravitational leptogenesis with pseudo-scalar-tensor coupling
复制标题
赝标量张量耦合的引力轻子发生重整化
DOI：
10.1088/1475-7516/2020/10/030
复制
发表时间：
2020
影响因子：
6.4
通讯作者：
Yamada Yusuke
中科院分区：
文献类型：
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作者：
Kamada Kohei;Kume Jun'ya;Yamada Yusuke
我们考虑使用引力 Chern-Simons 项对赝标量暴胀模型进行重正化。在这个模型中，轻子不对称性是由陈-西蒙斯项通过引力手性异常产生的手性引力波产生的。然而，众所周知，引力陈-庞特里亚金密度期望值以及由此产生的轻子数密度的朴素估计取决于紫外线截止尺度，这引发了对其有效性的质疑。在本文中，我们提出了一种重新标准化 Chern-Pontryagin 密度期望值的方法，以消除 UV 截止依赖性。我们还讨论了采用最小减法方案时的重整化轻子数密度以及引力轻子生成场景的可行性。
We consider the renormalization in the pseudo-scalar inflation models with the gravitational Chern-Simons term. In this model, lepton asymmetry is generated from the chiral gravitational waves produced due to the Chern-Simons term through the gravitational chiral anomaly. However, it is known that the naive estimate of the expectation value of the gravitational Chern-Pontryagin density as well as the resultant lepton number density depend on the UV-cutoff scale, which raises a question on their validity. In this paper, we propose a way to renormalize the expectation value of the Chern-Pontryagin density to remove the UV-cutoff dependence. We also discuss the renormalized lepton number density when we adopt the minimal subtraction scheme and the viability of the gravitational leptogenesis scenario.