Solutions to the 2-dimensional isothermal Euler–Poisson equations with a cosmological constant

Solutions to the cosmological constant problems

We critically review several recent approaches to solving the two cosmological constant problems. The ‘‘old’’ problem is the discrepancy between the observed value of rL and the large values suggested by particle physics models. The second problem is the ‘‘time coincidence’’ between the epoch of galaxy formation tG and the epoch of L domination tL . It is conceivable that the ‘‘old’’ problem ca...

Static Spherically Symmetric Solutions of SU(2) Einstein Yang Mills Equations with Positive Cosmological Constant

Eleven spherically symmetric constant density solutions with cosmological constant

Einstein’s field equations with cosmological constant are analysed for a static, spherically symmetric perfect fluid having constant density. Five new global solutions are described. One of these solutions has the Nariai solution joined on as an exterior field. Another solution describes a decreasing pressure model with exterior Schwarzschild-de Sitter spacetime having decreasing group orbits a...

Diluting Solutions of the Cosmological Constant Problem

We discuss the cosmological constant problem in the context of higher codimension brane world scenarios with infinite-volume extra dimensions.

Asymptotics of solutions of the Einstein equations with positive cosmological constant

A positive cosmological constant simplifies the asymptotics of forever expanding cosmological solutions of the Einstein equations. In this paper a general mathematical analysis on the level of formal power series is carried out for vacuum spacetimes of any dimension and perfect fluid spacetimes with linear equation of state in spacetime dimension four. For equations of state stiffer than radiat...