Chapter 2 Exploring the Components of the Universe Through Higher-Order Weak Lensing Statistics Higher-Order Weak Lensing Statistics

Abstract

Our current cosmological model, backed by a large body of evidence from a variety of different cosmological probes (for example, see [1, 2]), describes a Universe comprised of

around 5% normal baryonic matter, 22% cold dark matter and 73% dark energy. While many

cosmologists accept this so-called concordance cosmology – the ΛCDM cosmological model

– as accurate, very little is known about the nature and properties of these dark components

of the Universe.

Studies of the cosmic microwave background (CMB), combined with other observational

evidence of big bang nucleosynthesis indicate that dark matter is non-baryonic. This

supports measurements on galaxy and cluster scales, which found evidence of a large

proportion of dark matter. This dark matter appears to be cold and collisionless, apparent

only through its gravitational effects.