3,988 research outputs found
Gauge Symmetry, T-Duality and Doubled Geometry
String compactifications with T-duality twists are revisited and the gauge
algebra of the dimensionally reduced theories calculated. These reductions can
be viewed as string theory on T-fold backgrounds, and can be formulated in a
`doubled space' in which each circle is supplemented by a T-dual circle to
construct a geometry which is a doubled torus bundle over a circle. We discuss
a conjectured extension to include T-duality on the base circle, and propose
the introduction of a dual base coordinate, to give a doubled space which is
locally the group manifold of the gauge group. Special cases include those in
which the doubled group is a Drinfel'd double. This gives a framework to
discuss backgrounds that are not even locally geometric.Comment: 16 page
On Type IIA geometries dual to N = 2 SCFTs
We provide explicit solutions of Type IIA supergravity which are believed to
be dual to N = 2 superconformal four dimensional gauge theories. These explicit
solutions are based on the general ansatz for such a type of backgrounds
introduced by Gaiotto and Maldacena.Comment: 23 pages, 10 figures; minor corrections, references correcte
The supersymmetric Penrose transform in six dimensions
We give a supersymmetric extension to the six-dimensional Penrose transform
and give an integral formula for the on-shell (0, 2) supermultiplet. The
relationship between super fields on space-time and twistor space is clarified
and the space-time superfield constraint equations are derived from the
geometry of supertwistor space. We also explain the extension to more general
(0,n) supermultiplets and give twistor actions for these theories.Comment: 20 page
Environmental justice, capabilities, and the theorization of well-being
Environmental justice (EJ) scholarship is increasingly framing justice in terms of capabilities. This paper argues that capabilities are fundamentally about well-being and as such there is a need to more explicitly theorize well-being. We explore how capabilities have come to be influential in EJ and how well-being has been approached so far in EJ specifically and human geography more broadly. We then introduce a body of literature from social psychology which has grappled theoretically with questions about well-being, using the insights we gain from it to reflect on some possible trajectories and challenges for EJ as it engages with well-being
Securities Regulation -- Challenging the Short Form Merger Through Rule 10b-5 and the Corporate Purpose Doctrine
Bi-algebras, generalised geometry and T-duality
A study of sigma models whose target space is a group G that admits a
compatible Poisson structure is presented. The natural action of O(D,D;Z) on
the generalised tangent bundle TG+T*G and a generalisation of the Courant
bracket that appears are reviewed. This background provides a concrete example
where the generalised geometry and doubled geometry descriptions are both well
understood. Connections between the two formalisms are discussed and the
world-sheet theory from Hamiltonian and Lagrangian perspectives is
investigated. The comparisons between the approaches given by generalised
geometry and doubled geometry suggest possible ways of generalising the
analysis beyond the known examples.Comment: 43 page
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