Dark Matter Particles May Be Fewer Due to Effect of "Dilaton"

Research at King's College, London that is published in BioMed Central shows that theories of the properties of dark matter may be generating models that overestimate the role of supersymmetry neutralinos by neglecting the influence of dilatons.

Dilatons are hypothetical particles predicted by superstring supersymmetry models. Dilatons have zero mass and zero spin. Their importance in physics relates to the attempts by scientists to develop a theory of everything, that includes all the four universal forces--gravity, weak nuclear force, strong nuclear force and electromagnetic force--and all universal particles, known and as yet unknown.

Neutralinos are a more well known hypothetical particle that is also predicted by superstring supersymmetry models--one of the attempts at developing a theory of everything. Superstring supersymmetry models state that all Standard Model matter particles have partner "shadow" force carrier particles with the same quantum number but different energic spin, with the reverse also being true: every "shadow" particle has a matter particle. In other words, there is a one-on-one, two-directional relationship between matter particles and corresponding shadow force carriers. For example, for every matter particle called a quark there is a shadow force carrier called a squark.

At a second, later singular point in time, matter and energy ceased interacting with each other. This moment came when the universe had cooled down enough to allow electrons and protons to bond to form hydrogen atoms, which are the first of the visible matter atoms. At this time--the time of the forming of matter--the density of dark matter particles such as the neutralino--which are as yet unidentified and only hypothesized--was "frozen," left in a fixed state without further interaction with matter particles except through gravity. This frozen density of dark matter is referred to as the relic abundance.