String theory leads to a flavor scheme where modular symmetries play a crucial role. Together with the traditional flavor symmetries they combine to an eclectic flavor group, which we determine via outer automorphisms of the Narain space group. Unbroken flavor symmetries are subgroups of this eclectic group and their size depends on the location in moduli space. This mechanism of local flavor unification allows a different flavor structure for different sectors of the theory (such as quarks and leptons) and also explains the spontaneous breakdown of flavor- and $\mathcal{CP}$-symmetries (via a motion in moduli space). We derive the modular groups, including $\mathcal{CP}$ and R-symmetries, for different sub-sectors of six-dimensional string compactifications and determine the general properties of the allowed flavor groups from this top-down perspective. It leads to a very predictive flavor scheme that should be confronted with the variety of existing bottom-up constructions of flavor symmetry in order to clarify which of them could have a consistent top-down completion.

弦论产生了一种风味方案，其中模块化对称性起着至关重要的作用。与传统的风味对称性一起，它们组合成折衷的风味组，我们通过Narain空间组的外部自同构来确定折衷的风味组。不间断的风味对称性是该折衷组的子组，其大小取决于模空间中的位置。这种局部风味统一的机制为理论的不同部门（如夸克和轻子）提供了不同的风味结构，并且还解释了风味和自发性的自发分解。$\mathcal{CP}$-对称（通过模空间中的运动）。我们推导出模块化组，包括$\mathcal{CP}$和R-对称性，用于六维弦压实的不同子领域，并从此自上而下的角度确定允许的风味组的一般属性。这导致了一种非常可预测的风味方案，应该面对各种现有的自下而上的风味对称结构，以阐明其中哪些可以具有一致的自上而下的完成效果。