Dark side of the universe in the Stephani cosmology

We investigate the late time acceleration of the universe in the context of the Stephani model. This solution generalizes those of Friedmann-Lemaitre-Robertson-Walker (FLRW) in such a way that the spatial curvature is a function of of time. We show that the inhomogeneity of the models can lead to an accelerated evolution of the universe that is analogous to that obtained with FLRW models through a cosmological constant or any exotic component for matter.Comment: 8 pages, 2 figure, many improvements; to appear in European Physical Journal

Possibility of observing MSSM charged Higgs in association with a W boson at LHC

Possibility of observing associated production of charged Higgs and W boson in the framework of MSSM at LHC is studied. Both leptonic and hadronic decays of W boson are studied while the charged Higgs boson is considered to decay to a $\tau$ lepton and a neutrino. Therefore two search categories are defined based on the leptonic and hadronic final states, i.e. $\ell \tau+E^{miss}_{T}$ and $jj \tau+E^{miss}_{T}$ where $\ell=e$ or $\mu$ and $j$ is a light jet from $W$ decay. The discovery chance of the two categories is evaluated at an integrated luminosity of 300 \invfb at LHC. It is shown that both leptonic and hadronic final states have the chance of discovery at high \tanb. Finally $5\sigma$ and $3\sigma$ contours are provided for both search categories.Comment: 20 pages, 19 figure