In this paper, we propose a homogeneous curvaton mechanism that operates during the preheating process and in which the effective mass is running (i.e., its potential consists of a coupling term and an exponential term whose contribution is subdominant thereto). This mechanism can be classified into either narrow resonance or broad resonance cases, with the spectral index of the curvaton consituting the deciding criteria. The inflationary potential is that of chaotic inflation (i.e., a quadratic potential), which could result in a smooth transition into the preheating process. The entropy perturbations are converted into curvature perturbations, which we validate using the formalism. By neglecting the exponential term's contribution to the curvaton potential, we calculate the power spectrum and the nonlinear non-Gaussian parameter . Our calculations analytically show that these two observables are independent of the inflaton potential. Finally, when the curvaton decays (and the inflaton field vanishes), the exponential potential approaches a constant value similar to that of the cosmological constant, which may play the role of dark energy.

For the n − 1 dimensional FRW domain wall universe induced by n dimensional charged dilaton black hole, its movement formula in the bulk can be rewrite as the expansion or collapsing of domain wall. By analysing, we found that in this static AdS space, the cosmologic behaviour of domain wall is particularly single. Even more surprising, it exists an anomaly that the domain wall has a motion area outside of horizon, in which it cannot be explained by our classical theory.

Using ideas of cosmological perturbation theories, we make general linear stability analysis of dynamic thin-shell wormholes constructed by cutting-and-pasting two buildingblock spacetimes at arbitrary joining shell radius. We observed that in appropriate parameter choices, dynamical thin shell wormholes following from such a cut-and-paste procedure can be kept stable during the whole evolution process towards the final extremal point on which the joining shell radius reaches on static values. Our work forms a valuable complementarity to previous analysis basing on virtual spherical perturbations around the born-static configuration of the wormholes.

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