Course of lectures at the XIII Canary Islands Winter School of Astrophysics, "Cosmochemistry: The Melting Pot of Elements" (November 19 - 30, 2001; Tenerife, Canary Islands, Spain).
astro-ph/0208186

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PRIMORDIAL ALCHEMY:
FROM THE BIG BANG TO THE PRESENT UNIVERSE

Gary Steigman


Departments of Physics and Astronomy,
The Ohio State University, Columbus, OH 43210, USA


Abstract. Of the light nuclides observed in the universe today, D, 3He, 4He, and 7Li are relics from its early evolution. The primordial abundances of these relics, produced via Big Bang Nucleosynthesis (BBN) during the first half hour of the evolution of the universe provide a unique window on Physics and Cosmology at redshifts ~ 1010. Comparing the BBN-predicted abundances with those inferred from observational data tests the consistency of the standard cosmological model over ten orders of magnitude in redshift, constrains the baryon and other particle content of the universe, and probes both Physics and Cosmology beyond the current standard models. These lectures are intended to introduce students, both of theory and observation, to those aspects of the evolution of the universe relevant to the production and evolution of the light nuclides from the Big Bang to the present. The current observational data is reviewed and compared with the BBN predictions and the implications for cosmology (e.g. universal baryon density) and particle physics (e.g. relativistic energy density) are discussed. While this comparison reveals the stunning success of the standard model(s), there are currently some challenges which leave open the door for more theoretical and observational work with potential implications for astronomy, cosmology, and particle physics.


Table of Contents

INTRODUCTION

THE EARLY EVOLUTION OF THE UNIVERSE
Redshift
Dynamics
Counting Relativistic Degrees of Freedom
"Extra" Relativistic Energy

BIG BANG NUCLEOSYNTHESIS AND THE PRIMORDIAL ABUNDANCES
An Early Universe Chronology
Neutron - Proton Interconversion
Building The Elements
The SBBN-Predicted Abundances
Variations On A Theme: Non-Standard BBN

OBSERVATIONAL STATUS OF THE RELIC ABUNDANCES
Deuterium
Helium-3
Helium-4
Lithium-7

CONFRONTATION OF THEORETICAL PREDICTIONS WITH OBSERVATIONAL DATA
Deuterium - The Baryometer Of Choice
SBBN Baryon Density - The Baryon Density At 20 Minutes
CMB Baryon Density - The Baryon Density At A Few Hundred Thousand Years
The Baryon Density At 10 Gyr
Baryon Density Concordance
Testing The Consistency Of SBBN

BBN IN NON-STANDARD MODELS
Degenerate BBN

SUMMARY

REFERENCES

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