CMB Multi-pole anisotrophy

Many cosmologists advocate reviving the cosmological constant term on theoretical grounds, as a way to explain the rate of expansion of the universe. Modern field theory associates this term with the energy density of the vacuum. For this energy density to be comparable to other forms of matter in the universe, it would require new physics theories. So the addition of a cosmological constant term has profound implications for particle physics and our understanding of the fundamental forces of nature

https://wmap.gsfc.nasa.gov/universe/uni_matter.html

Anti--de Sitter spacetime is important in general relativity and modern field theory. We review its geometrical features and properties of light signals and free particles moving in it. Applying only elementary tools of tensor calculus we derive \textit{ab initio\/} all these properties and show that they are really weird. One finds superluminal velocities of light and particles, infinite particle energy necessary to escape at infinite distance and spacetime regions inaccessible by a free fall, though reachable by an accelerated spaceship. Radial timelike geodesics are identical to the circular ones and actually all timelike geodesics are identical to one circle in a fictitious five--dimensional space. Employing the latter space one is able to explain these bizarre features of anti--de Sitter spacetime; in this sense the spacetime is not self--contained. This is not a physical world.