Empirical Modelings
There are empirical approaches that predict the overall SED of the EBL in the local Universe as well as its evolution over time. These types of modeling can be divided in four different categories according to.
(i) Forward evolution, which begins with cosmological initial conditions and follows a forward evolution with time by means of semi-analytical models of galaxy formation.
(ii) Backward evolution, which begins with existing galaxy populations and extrapolates them backwards in time.
(iii) Evolution of the galaxy populations that is inferred over a range of redshifts. The galaxy evolution is inferred here using some quantity derived from observations such as the star formation rate density of the universe.
(iv) Evolution of the galaxy populations that is directly observed over the range of redshifts that contribute significantly to the EBL.
Read more about this topic: Extragalactic Background Light
Famous quotes containing the word empirical:
“To develop an empiricist account of science is to depict it as involving a search for truth only about the empirical world, about what is actual and observable.... It must involve throughout a resolute rejection of the demand for an explanation of the regularities in the observable course of nature, by means of truths concerning a reality beyond what is actual and observable, as a demand which plays no role in the scientific enterprise.”
—Bas Van Fraassen (b. 1941)