论文标题
排除光斧：写作在墙上
Ruling out light axions: the writing is on the wall
论文作者
论文摘要
我们对QCD轴模型的域壁问题进行了回顾，该模型在Peccei-Quinn对称性下充满了一个夸克。在通货膨胀期间或之后，对称性破裂会导致域壁网络形成，如果涉及统治宇宙，这将导致宇宙灾难。由于普朗克量表抑制了不可硝基分散的操作员，因此可以通过在轴上电位中调用倾斜度的“倾斜”来使网络变得不稳定。或者，通货膨胀期间轴心场随机行走可能会产生一个有利于堕落真空的偏见，但我们发现这种机制在实践中是无关紧要的。然后，壁网衰减产生的轴子丰度的考虑要求Peccei-Quinn量表相当低 - 因此排除了例如质量低于11 MEV的DFSZ轴，实际上大多数实验搜索都聚焦。
We revisit the domain wall problem for QCD axion models with more than one quark charged under the Peccei-Quinn symmetry. Symmetry breaking during or after inflation results in the formation of a domain wall network which would cause cosmic catastrophe if it comes to dominate the Universe. The network may be made unstable by invoking a `tilt' in the axion potential due to Planck scale suppressed non-renormalisable operators. Alternatively the random walk of the axion field during inflation can generate a `bias' favouring one of the degenerate vacua, but we find that this mechanism is in practice irrelevant. Consideration of the axion abundance generated by the decay of the wall network then requires the Peccei-Quinn scale to be rather low -- thus ruling out e.g. the DFSZ axion with mass below 11 meV, where most experimental searches are in fact focussed.
