The Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2AZ, United Kingdom.
Theoretische Natuurkunde, Vrije Universiteit Brussel, and the International Solvay Institutes, Pleinlaan 2, B-1050 Brussels, Belgium.
Phys Rev Lett. 2018 May 25;120(21):211601. doi: 10.1103/PhysRevLett.120.211601.
We construct the exceptional sigma model: a two-dimensional sigma model coupled to a supergravity background in a manifestly (formally) E_{D(D)}-covariant manner. This formulation of the background is provided by exceptional field theory (EFT), which unites the metric and form fields of supergravity in E_{D(D)} multiplets before compactification. The realization of the symmetries of EFT on the world sheet uniquely fixes the Weyl-invariant Lagrangian and allows us to relate our action to the usual type-IIA fundamental string action and a form of the type-IIB (m, n) action. This uniqueness "predicts" the correct form of the couplings to gauge fields in both Neveu-Schwarz and Ramond sectors, without invoking supersymmetry.
我们构建了一个特殊的 sigma 模型：一个二维 sigma 模型与一个超引力背景以显式（形式上） E_{D(D)}协变的方式耦合。这种背景的表述是由特殊场论（EFT）提供的，它在紧致化之前将超引力的度量和形式场统一在 E_{D(D)}多重态中。EFT 的对称性在世界面上的实现唯一地确定了 Wey 不变的拉格朗日量，并使我们能够将我们的作用与通常的 II 型 A 基本弦作用和 IIB（m，n）作用的一种形式联系起来。这种唯一性“预测”了对 Neveu-Schwarz 和 Ramond 扇区中规范场的耦合的正确形式，而无需引入超对称性。
