Dark matter in the Universe

Conference · Fri Mar 01 00:00:00 EST 1991

OSTI ID:5541027

Turner, M S ^[1]

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1. Fermi National Accelerator Lab., Batavia, IL (USA) Chicago Univ., IL (USA). Enrico Fermi Inst.

What is the quantity and composition of material in the universe This is one of the most fundamental questions we can ask about the universe, and its answer bears on a number of important issues including the formation of structure in the universe, and the ultimate fate and the earliest history of the universe. Moreover, answering this question could lead to the discovery of new particles, as well as shedding light on the nature of the fundamental interactions. At present, only a partial answer is at hand: most of the material in the universe does not give off detectable radiation, i.e., is dark;'' the dark matter associated with bright galaxies contributes somewhere between 10% and 30% of the critical density (by comparison luminous matter contributes less than 1%); baryonic matter contributes between 1.1% and 12% of critical. The case for the spatially-flat, Einstein-de Sitter model is supported by three compelling theoretical arguments -- structure formation, the temporal Copernican principle, and inflation -- and by some observational data. If {Omega} is indeed unity--or even just significantly greater than 0.1--then there is a strong case for a universe comprised of nonbaryonic matter. There are three well motivated particle dark-matter candidates: an axion of mass 10{sup {minus}6} eV to 10{sup {minus}4} eV; a neutralino of mass 10 GeV to about 3 TeV; or a neutrino of mass 20 eV to 90 eV. All three possibilities can be tested by experiments that are either being planned or are underway. 71 refs., 6 figs.

• Research Organization: Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
• Sponsoring Organization: USDOE; USDOE, Washington, DC (United States)
• DOE Contract Number: AC02-76CH03000
• OSTI ID: 5541027
• Report Number(s): FNAL/C-91/78-A; CONF-901141-6; ON: DE91014863
• Resource Relation: Conference: International conference on trends in astroparticle physics, Santa Monica, CA (United States), 26 Nov - 1 Dec 1990
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
UNIVERSE
NONLUMINOUS MATTER
AXIONS
NEUTRINOS
NUCLEOSYNTHESIS
RELICT RADIATION
BOSONS
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
FERMIONS
GOLDSTONE BOSONS
LEPTONS
MASSLESS PARTICLES
MATTER
MICROWAVE RADIATION
POSTULATED PARTICLES
RADIATIONS
SYNTHESIS
640102* - Astrophysics & Cosmology- Stars & Quasi-Stellar
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640106 - Astrophysics & Cosmology- Cosmology
645200 - High Energy Physics- Particle Interactions & Properties-Theoretical