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A status report on the standard model of big bang nucleosynthesis (BBN) in the post-WMAP era is presented. With the value of the baryon-to-photon ratio determine to relatively high precision by WMAP, standard BBN no longer has any free parameters. In this context, the theoretical prediction for the abundances of D, He4, and Li7 is discussed and compared to the observational determination of the light nuclides. While concordance for D and He4 are satisfactory, the prediction for Li7 exceeds the observational determination by a factor of about four. Possible solutions to this problem are also discussed. [ABSTRACT FROM AUTHOR]

An update on the standard model of big bang nucleosynthesis (BBN) is presented. With the value of the baryon-tophoton ratio determined to high precision by WMAP, standard BBN is a parameter-free theory. In this context, the theoretical prediction for the abundances of D, 4He, and 7Li is discussed and compared to their observational determination. While concordance for D and 4He is satisfactory, the prediction for 7Li exceeds the observational determination by a factor of about four. Possible solutions to this problem are discussed. [ABSTRACT FROM AUTHOR]

The constrained minimal supersymmetric standard model (CMSSM) contains a natural dark matter candidate, the neutralino. The relic density of dark matter accounts for the WMAP matter density when either 1) the neutralino and stau are nearly degenerate (this parameter space is then referred to as the co-annihilation region), 2) the mass of the neutralino is close to 1/2 the mass of the Higgs pseudo-scalar (the funnel region) or 3) the neutralino picks up a significant Higgsino component (as in the focus point region). I will discuss a recent frequentist analysis of the CMSSM which favors the co-annihilation region. I will also discuss the calculated neutralino-nucleon elastic scattering cross section and its uncertainties. Models considered will be the CMSSM and variants in which the universality of the scalar Higgs masses is relaxed. [ABSTRACT FROM AUTHOR]

A comparison is made between accelerator and direct detection constraints in constrained versions of the minimal supersymmetric standard model. Models considered are based on mSUGRA, where scalar and gaugino masses are unified at the GUT scale. In addition, the mSUGRA relation between the (unified) A and B parameters is assumed, as is the relation between m0 and the gravitino mass. Also considered are models where the latter two conditions are dropped (the CMSSM), and a less constrained version where the Higgs soft masses are not unified at the GUT scale (the NUHM). © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

An overview of the standard model of big bang nucleosynthesis (BBN) in the post-WMAP era is presented. With the value of the baryon-to-photon ratio determined to relatively high precision by WMAP, standard BBN no longer has any free parameters. In this context, the theoretical prediction for the abundances of D, 3He, 4He, and 7Li is discussed. The observational determination of the light nuclides is also discussed. While, the D and 4He observations are concordant with BBN predictions, 7Li remains discrepant with the CMB-preferred baryon density and possible explanations are reviewed. Finally, moving beyond the standard model, primordial nucleosynthesis constraints on early universe and particle physics are also briefly discussed. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]