A New Approach to Non-Abelian Hydrodynamics

We present a new approach to describe hydrodynamics carrying non-Abelian macroscopic degrees of freedom. Based on the Kaluza-Klein compactification of a higher-dimensional neutral dissipative fluid on a group manifold, we obtain a d=4 colored dissipative fluid coupled to Yang-Mills gauge field. We calculate the transport coefficients of the new fluid, which show the non-Abelian character of the gauge group. In particular, we obtain group-valued terms in the gradient expansions and response quantities such as the conductivity matrix and the chemical potentials. While using SU(2) for simplicity, this approach is applicable to any gauge group. Resulting a robust description of non-Abelian hydrodynamics, we discuss some links between this system and quark-gluon plasma and fluid/gravity duality.Comment: 41 pages (31 + appendices), 1 figure. V2: Minor modifications, some typos fixed and references adde

TT-folds from Yang-Baxter deformations

Yang-Baxter (YB) deformations of type IIB string theory have been well studied from the viewpoint of classical integrability. Most of the works, however, are focused upon the local structure of the deformed geometries and the global structure still remains unclear. In this work, we reveal a non-geometric aspect of YB-deformed backgrounds as $T$-fold by explicitly showing the associated $\mathrm{O}(D,D;\mathbb{Z})$ $T$-duality monodromy. In particular, the appearance of an extra vector field in the generalized supergravity equations (GSE) leads to the non-geometric $Q$-flux. In addition, we study a particular solution of GSE that is obtained by a non-Abelian $T$-duality but cannot be expressed as a homogeneous YB deformation, and show that it can also be regarded as a $T$-fold. This result indicates that solutions of GSE should be non-geometric quite in general beyond the YB deformation.Comment: 47 page

Weaving the Exotic Web

String and M-theory contain a family of branes forming U-duality multiplets. In particular, standard branes with codimension higher than or equal to two, can be explicitly found as supergravity solutions. However, whether domain-wall branes and space-filling branes can be found as supergravity solutions is still unclear. In this paper, we firstly provide a full list of exotic branes in type II string theory or M-theory compactified to three or higher dimensions. We show how to systematically obtain backgrounds of exotic domain-wall branes and space-filling branes as solutions of the double field theory or the exceptional field theory. Such solutions explicitly depend on the winding coordinates and cannot be given as solutions of the conventional supergravity theories. However, as the domain-wall solutions depend linearly on the winding coordinates, we describe them as solutions of deformed supergravities such as the Romans massive IIA supergravity or lower-dimensional gauged supergravities. We establish explicit relations among the domain-wall branes, the mixed-symmetry potentials, the locally non-geometric fluxes, and deformed supergravities.Comment: 72 pages + 28 pages of appendices; v2: typos corrected, references added, a Mathematica notebook added (which generates Tables in Appendix C); v3: typos corrected, references added, JHEP published versio

Open Strings in IIB Orientifold Reductions

We consider type IIB compactifications on a general 4D group manifold with different types of possible spacetime filling O-planes and the corresponding D-branes parallel to them. Once fluxes allowed by the associated orientifold projection are included, a 6D $\mathcal{N}=(1,1)$ gauged supergravity is obtained. In this paper we show how the consistent coupling to dynamical open strings living on the spacetime filling D-branes may be captured by the inclusion of extra vector multiplets and extra embedding tensor deformations on the gauged supergravity side. As a result, the quadratic constraints on the embedding tensor consistently reproduce the source corrected 10D Bianchi identities. Furthermore, the field strength modifications induced by the open string sector could potentially be understood as U-dual versions of the Green-Schwarz terms. Finally, the entire scalar potential of the theory exactly matches the one obtained from reduction of the bulk action plus the source contributions.Comment: 45 pages, 1 figur

6D (1,1) gauged supergravities from orientifold compactifications

We study dimensional reductions of M-theory/type II strings down to 6D in the presence of fluxes and spacetime filling branes and orientifold planes of different types. We classify all inequivalent orientifold projections giving rise to N = (1, 1) supergravities in 6D and work out the embedding tensor/fluxes dictionary for each of those. Finally we analyze the set of vacua for the different classes of reductions and find an abundance of "no-scale" type Minkowski vacua, as well as a few novel examples of (A)dS extrema