论文标题
具有增强的对称性
Exceptional nonrelativistic effective field theories with enhanced symmetries
论文作者
论文摘要
我们启动了Nambu-Goldstone（NG）玻色子的非层次有效场理论（EFT）的分类，并具有一组冗余，坐标依赖性的对称性。与相对论的情况类似，这种EFT是“特殊”理论的天然候选者，其散射幅度具有增强的软限制，即在长波长下具有比仅基于Adler零的存在的预期的动量功率更高的尺度。我们框架的起点是在时空翻译和空间旋转下的不变性假设。然而，该设置足以容纳各种非平凡的运动代数，包括Poincare，Galilei（或Bargmann）和Carroll代数。我们的主要结果是对两种无限类别的非典型理论的非宗派版本的明确构造：多 - 加利利亚和多风味迪拉克 - 出生式侵略（DBI）理论。在这两种情况下，我们都发现了新颖的wess-zumino术语，在其相对论对应物中都不存在，从而非凡地意识到作用于NG领域的偏移对称性。我们演示了如何使Galileon和DBI理论的对称性与（某些）NG模式的非偏差，二次分散关系兼容。
We initiate the classification of nonrelativistic effective field theories (EFTs) for Nambu-Goldstone (NG) bosons, possessing a set of redundant, coordinate-dependent symmetries. Similarly to the relativistic case, such EFTs are natural candidates for "exceptional" theories, whose scattering amplitudes feature an enhanced soft limit, that is, scale with a higher power of momentum at long wavelengths than expected based on the mere presence of Adler's zero. The starting point of our framework is the assumption of invariance under spacetime translations and spatial rotations. The setup is nevertheless general enough to accommodate a variety of nontrivial kinematical algebras, including the Poincare, Galilei (or Bargmann) and Carroll algebras. Our main result is an explicit construction of the nonrelativistic versions of two infinite classes of exceptional theories: the multi-Galileon and the multi-flavor Dirac-Born-Infeld (DBI) theories. In both cases, we uncover novel Wess-Zumino terms, not present in their relativistic counterparts, realizing nontrivially the shift symmetries acting on the NG fields. We demonstrate how the symmetries of the Galileon and DBI theories can be made compatible with a nonrelativistic, quadratic dispersion relation of (some of) the NG modes.
