It has been argued in the literature that if a universe is expanding with an accelerating rate indefinitely, it presents a challenge to string theories due to the existence of event horizons. We study the fate of a currently accelerating universe. We show that the universe will continue to accelerate indefinitely if the parameter ω = p/ρ of the equation of state is a constant, no matter how man...

We present a general slow-roll formalism within braneworld-motivated cosmologies with nonstandard effective Friedmann equations. Full towers of parameters involving either the inflaton potential or the Hubble parameter are constructed and the dynamics of non-tachyonic and tachyonic fields are considered in detail; exact cosmological solutions and the inflationary attractor condition are provide...

This paper provides an overview of the key features of the accelerating power-based power system stabilizer (PSS). This design of PSS has been adopted by most major manufacturers and is integrated as an option in many digital excitation systems. The structure has been the topic of numerous published papers discussing the choice of input signals, parameter selection and advantages over other con...

To find an optimum accelerating parameter of the SOR method is important and a difficult part of the problem. It is more difficult to estimate many optimum parameters of the GSOR method. In this talk, we propose a new algorithm to estimate the optimum parameters of the GSOR method. The key point to estimate these parameters is using a preconditioned matrix constructed by a part of the coefficie...

The wake fields produced by an intense, short laser pulse propagating in a plasma channel with an arbitrary density profile are investigated. Plasma channels, viewed as accelerating structures, have many desirable features that are not shared by a homogeneous plasma. Moreover, they are becoming experimentally realizable. As part of an overall program to analyze plasma channels as accelerating s...

Newton potential for DGP brane-world scenario is examined when the extra dimension is semi-infinite. The final form of the potential involves a self-adjoint extension parameter α, which plays a role of an additional mass (or distance) scale. The striking feature of Newton potential in this setup is that the potential behaves as seven-dimensional in long range when α is nonzero. For small α ther...

This Resource Letter provides a guide to the literature on dark energy and the accelerating universe. It is intended to be of use to researchers, teachers, and students at several levels. Journal articles, books, and websites are cited for the following topics: Einstein’s cosmological constant, quintessence or dynamical scalar fields, modified cosmic gravity, relations to high energy physics, c...

An accelerating flat universe with a variable cosmological term is obtained in the Robertson-Walker metric. The variable cosmological term is defined by the correction terms of the metric tensor field. Simple solutions of the scale factor and the cosmological term are shown. In this model of the universe, the magnitude-redshift relation is analytically studied to see if the model reproduces the...

Research on human online activities usually assumes that total activity T increases linearly with active population P , that is, T ∝ P (γ = 1). However, we find examples of systems where total activity grows faster than active population. Our study shows that the power law relationship T ∝ P (γ > 1) is in fact ubiquitous in online activities such as micro-blogging, news voting and photo tagging...

High redshift supernova magnitudes of current interest are reexamined. The magnitudes conventionally reported include an additive parameter called the extinction coefficient. We find that the extinction coefficients of a popular “gold” set are well correlated with the deviation of magnitudes from standard Hubble diagrams. The statistical significance of the extinction-acceleration correlation h...