Primordial isocurvature baryon model
Encyclopedia
A primordial isocurvature baryon model, or PIB model, is a theoretical model
describing the development of the early universe
. It may be contrasted with the a cold dark matter model, or CDM model. The PIB model was proposed in 1987 by Jim Peebles
as an alternative to the CMB model which does not necessitate the existence of exotic dark matter
. PIB models, which ascribe all cosmic density perturbations to isocurvature modes, predict results that are inconsistent with the observational data.
Scientific modelling
Scientific modelling is the process of generating abstract, conceptual, graphical and/or mathematical models. Science offers a growing collection of methods, techniques and theory about all kinds of specialized scientific modelling...
describing the development of the early universe
Universe
The Universe is commonly defined as the totality of everything that exists, including all matter and energy, the planets, stars, galaxies, and the contents of intergalactic space. Definitions and usage vary and similar terms include the cosmos, the world and nature...
. It may be contrasted with the a cold dark matter model, or CDM model. The PIB model was proposed in 1987 by Jim Peebles
Jim Peebles
Phillip James Edwin Peebles is a Canadian-American physicist and theoretical cosmologist who is currently the Albert Einstein Professor Emeritus of Science at Princeton University. Peebles was born in Winnipeg and completed his bachelor's degree at the University of Manitoba...
as an alternative to the CMB model which does not necessitate the existence of exotic dark matter
Dark matter
In astronomy and cosmology, dark matter is matter that neither emits nor scatters light or other electromagnetic radiation, and so cannot be directly detected via optical or radio astronomy...
. PIB models, which ascribe all cosmic density perturbations to isocurvature modes, predict results that are inconsistent with the observational data.