https://hal-cea.archives-ouvertes.fr/cea-01295157Aldazabal, G.G.AldazabalGraña, M.M.GrañaIPHT - Institut de Physique Théorique - UMR CNRS 3681 - CEA - Commissariat à l'énergie atomique et aux énergies alternatives - Université Paris-Saclay - CNRS - Centre National de la Recherche ScientifiqueIguri, S.S.IguriMayo, M.M.MayoMenzies School of Health Research [Australia] - Charles Darwin University [Australia]Nuñez, C.C.NuñezRosabal, J. A.J. A.RosabalUNICEN - Universidad Nacional del Centro de la Provincia de Buenos Aires [Buenos Aires]Enhanced gauge symmetry and winding modes in Double Field TheoryHAL CCSD2016[PHYS.HTHE] Physics [physics]/High Energy Physics - Theory [hep-th]De Laborderie, Emmanuelle2016-03-30 14:37:292022-08-05 10:29:502016-03-30 15:20:40enJournal articleshttps://hal-cea.archives-ouvertes.fr/cea-01295157/document10.1007/JHEP03(2016)093text/html; charset=utf-81We provide an explicit example of how the string winding modes can be incorporated in double field theory. Our guiding case is the closed bosonic string compactified on a circle of radius close to the self-dual point, where some modes with non-zero winding or discrete momentum number become massless and enhance the $U(1) \times U(1)$ symmetry to $SU(2) \times SU(2)$. We compute three-point string scattering amplitudes of massless and slightly massive states, and extract the corresponding effective low energy gauge field theory. The enhanced gauge symmetry at the self-dual point and the Higgs-like mechanism arising when changing the compactification radius are examined in detail. The extra massless fields associated to the enhancement are incorporated into a generalized frame with $\frac{O(d+3,d+3)}{O(d+3)\times O(d+3)}$ structure, where $d$ is the number of non-compact dimensions. We devise a consistent double field theory action that reproduces the low energy string effective action with enhanced gauge symmetry. The construction requires a truly non-geometric frame which explicitly depends on both the compact coordinate along the circle and its dual.