Cosmological implications of light element abundances: Theory

Conference · Tue Jun 01 00:00:00 EDT 1993 · Proceedings of the National Academy of Sciences of the United States of America; (United States)

OSTI ID:6200733

Schramm, D N ^[1]

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1. Univ. of Chicago, IL (United States) Fermi National Accelerator Lab., Batavia, IL (United States)

Primordial nucleosynthesis provides (with the microwave background radiation) one of the two quantitative experimental tests of the hot Big Bang cosmological model (versus alternative explanations for the observed Hubble expansion). The standard homogeneous-isotopic calculation fits the light element abundances ranging from [sup 1]H at 76% and [sup 4]He at 24% by mass through [sup 2]H and [sup 3]He at parts in 10[sup 5] down to [sup 7]Li at parts in 10[sup 10]. It is also noted how the recent Large Electron Positron Collider (and Stanford Linear Collider) results on the number of neutrinos (N[sub [nu]]) are a positive laboratory tests of this standard Big Bang scenario. The possible alternate scenario of quark-hadron-induced inhomogeneities is also discussed. It is shown that when this alternative scenario is made to fit the observed abundances accurately, the resulting conclusions on the baryonic density relative to the critical density ([Omega][sub b]) remain approximately the same as in the standard homogeneous case, thus adding to the robustness of the standard model and the conclusion that [Omega][sub b] [approx] 0.06. This latter point is the driving force behind the need for nonbaryonic dark matter (assuming total density [Omega][sub total] = 1) and the need for dark baryonic matter, since the density of visible matter [Omega][sub visible] < [Omega][sub b]. The recent Population II B and Be observations are also discussed and shown to be a consequence of cosmic ray spallation processes rather than primordial nucleosynthesis. The light elements and N[sub [nu]] successfully probe the cosmological model at times as early as 1 sec and a temperature (T) of [approx] 10[sup 10] K ([approx] 1 MeV). Thus, they provided the first quantitative arguments that led to the connections of cosmology to nuclear and particle physics. 79 refs., 4 figs.

• DOE Contract Number: FG02-91ER40606
• OSTI ID: 6200733
• Report Number(s): CONF-9203232-; CODEN: PNASA6; CNN: AST 90-22629; NAGW-1321
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (United States), Vol. 90:11; Conference: National Academy of Sciences (NAS) special colloquium on physical cosmology, Irvine, CA (United States), Mar 1992; ISSN 0027-8424
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
UNIVERSE
COSMOLOGICAL MODELS
ASTROPHYSICS
BACKGROUND RADIATION
BARYONS
HELIUM
HYDROGEN
LITHIUM
NEUTRINOS
NUCLEOSYNTHESIS
QUARKS
SPALLATION
ALKALI METALS
ELEMENTARY PARTICLES
ELEMENTS
FERMIONS
FLUIDS
GASES
HADRONS
LEPTONS
MASSLESS PARTICLES
MATHEMATICAL MODELS
METALS
NONMETALS
NUCLEAR REACTIONS
POSTULATED PARTICLES
RADIATIONS
RARE GASES
SYNTHESIS
661300* - Other Aspects of Physical Science- (1992-)