We review the production of the matter-antimatter asymmetry in the early Universe, that is baryogenesis, in out-of-equlibrium conditions induced by decays of heavy particles or the presence of phase boundaries. The most prominent examples are given by leptogenesis and electroweak baryogenesis, respectively, and for both cases, we derive the equations that govern the production of the asymmetries. We first use more intuitive arguments based on classical fluid equations in combination with quantum-field-theoretical effects of $CP$-violation. Then, in order to provide a more thorough approach that is well-suited for systematic improvements, we obtain the real-time evolution of the system of interest based on first principles, using the closed time-path approach. We thus aim to provide a simple and practicable scheme to set up phenomenological fluid equations as well as to provide a more thorough deduction of these. Necessary for baryogenesis are both, CP even as well as odd phases in the amplitudes. A possibility of generating the even phases is the coherent superposition of quantum states, i.e. mixing. These coherence effects are essential in resonant leptogenesis as well as in some scenarios of electroweak baryogenesis, and recent theoretical progress on asymmetries from out-of-equlibrium decays may also be applicable to baryogenesis at phase boundaries.

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为什么物质比反物质多？瘦素生成和电弱重子生成的计算方法

我们回顾了早期宇宙中物质-反物质不对称的产生，即重粒子衰变或相界存在引起的失衡条件下的重子发生。最突出的例子分别是瘦素生成和电弱重子生成，对于这两种情况，我们推导出控制不对称性产生的方程。我们首先使用基于经典流体方程的更直观的参数，并结合 $CP$ 违反的量子场理论效应。然后，为了提供更适合系统改进的更彻底的方法，我们使用封闭时间路径方法基于第一原理获得感兴趣系统的实时演化。因此，我们旨在提供一个简单可行的方案来建立现象学流体方程，并提供对这些方程的更彻底的推导。重子发生所必需的是振幅中的 CP 偶数和奇数相位。产生偶相的一种可能性是量子态的相干叠加，即混合。这些相干效应在共振轻质发生以及电弱重子发生的某些情况下是必不可少的，最近关于失衡衰变引起的不对称性的理论进展也可能适用于相边界处的重子发生。混合。这些相干效应在共振轻质发生以及电弱重子发生的某些情况下是必不可少的，最近关于失衡衰变引起的不对称性的理论进展也可能适用于相边界处的重子发生。混合。这些相干效应在共振轻质发生以及电弱重子发生的某些情况下是必不可少的，最近关于失衡衰变引起的不对称性的理论进展也可能适用于相边界处的重子发生。