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We consider a six-dimensional Einstein-Maxwell system compactified in an axisymmetric two-dimensional space with one capped regularized conical brane of codimension one. We study the cosmological evolution which is induced on the regularized brane as it moves in between known static bulk and cap solutions. Looking at the resulting Friedmann equation, we see that the brane cosmology at high energies is dominated by a five-dimensional rho^2 energy density term. At low energies, we obtain a Friedmann equation with a term linear to the energy density with, however, negative coefficient in the small four-brane radius limit (i.e. with negative effective Newtons constant). We discuss ways out of this problem.
We explore solutions of six dimensional gravity coupled to a non-linear sigma model, in the presence of co-dimension two branes. We investigate the compactifications induced by a spherical scalar manifold and analyze the conditions under which they a
We investigate the fermion condensate (FC) for a massive spinor field on background of the 5-dimensional locally anti-de Sitter (AdS) spacetime with a compact dimension and in the presence of a cosmic string carrying a magnetic flux. The FC is decomp
We discuss supergravity inflation in braneworld cosmology for the class of potentials $V(phi)=alpha phi^nrm{exp}(-beta^m phi^m)$ with $m=1,~2$. These minimal SUGRA models evade the $eta$ problem due to a broken shift symmetry and can easily accommoda
The cosmology of branes undergoing the self-tuning mechanism of the cosmological constant is considered. The equations and matching conditions are derived in several coordinate systems, and an exploration of possible solution strategies is performed.
We study the regularization of the codimension-2 singularities in six-dimensional Einstein-Maxwell axisymmetric models with warping. These singularities are replaced by codimension-1 branes of a ring form, situated around the axis of symmetry. We ass