General Perturbations for Braneworld Compactifications and the Six Dimensional Case - High Energy Physics - TheoryReport as inadecuate




General Perturbations for Braneworld Compactifications and the Six Dimensional Case - High Energy Physics - Theory - Download this document for free, or read online. Document in PDF available to download.

Abstract: Our main objective is to study how braneworld models of higher codimensiondiffer from the 5D case and traditional Kaluza-Klein compactifications. Wefirst derive the classical dynamics describing the physical fluctuations in awide class of models incorporating gravity, non-Abelian gauge fields, thedilaton and two-form potential, as well as 3-brane sources. Next, we use theseresults to study braneworld compactifications in 6D supergravity, focusing onthe bosonic fields in the minimal model; composed of the supergravity-tensormultiplet and the U1 gauge multiplet whose flux supports thecompactification. For unwarped models sourced by positive tension branes, aharmonic analysis allows us to solve the large, coupled, differential systemcompletely and obtain the full 4D spin-2,1 and 0 particle spectra, establishingmarginal stability and a qualitative behaviour similar to the smooth spherecompactification. We also find interesting results for models with negativetension branes; extra massless Kaluza-Klein vector fields can appear in thespectra, beyond those expected from the isometries in the internal space. Thesefields imply an enhanced gauge symmetry in the low energy 4D effective theoryobtained by truncating to the massless sector, which is explicitly broken ashigher modes are excited, until the full 6D symmetries are restored far abovethe Kaluza-Klein scale. Remarkably, the low energy effective theory does notseem to distinguish between a compactification on a smooth sphere and thesesingular, deformed spheres.



Author: S.L. Parameswaran, S. Randjbar-Daemi, A. Salvio

Source: https://arxiv.org/







Related documents