Exponential gravity

Journal Article · Tue Dec 15 00:00:00 EST 2009 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.80.123528· OSTI ID:21313583

Linder, Eric V ^[1]

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1. Berkeley Lab and University of California, Berkeley, California 94720 (United States) and Institute for the Early Universe, Ewha Womans University, Seoul (Korea, Republic of)

We investigate a f(R) modification of gravity that is exponential in the Ricci scalar R to explain cosmic acceleration. The steepness of this dependence provides extra freedom to satisfy solar system and other curvature regime constraints. With a parameter to alleviate the usual fine-tuning of having the modification strengthen near the present, the total number of parameters is only one more than {lambda}CDM. The resulting class of solutions asymptotes to w=-1 but has no cosmological constant. We calculate the dynamics in detail, examine the effect on the matter power spectrum, and provide a simple fitting form relating the two.

• OSTI ID: 21313583
• Journal Information: Physical Review. D, Particles Fields, Vol. 80, Issue 12; Other Information: DOI: 10.1103/PhysRevD.80.123528; (c) 2009 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE
ACCELERATION
COSMOLOGICAL CONSTANT
GRAVITATION
MATHEMATICAL SOLUTIONS
MATTER
SIMULATION
SOLAR SYSTEM
SPECTRA