Selfaccelerating warped braneworlds
Abstract
Braneworld models with induced gravity have the potential to replace dark energy as the explanation for the current accelerating expansion of the Universe. The original model of Dvali, Gabadadze, and Porrati (DGP) demonstrated the existence of a 'selfaccelerating' branch of background solutions, but suffered from the presence of ghosts. We present a new large class of braneworld models which generalize the DGP model. Our models have negative curvature in the bulk, allow a second brane, and have general brane tensions and localized curvature terms. We exhibit three different kinds of ghosts, associated to the graviton zero mode, the radion, and the longitudinal components of massive graviton modes. The latter two species occur in the DGP model, for negative and positive brane tension, respectively. In our models, we find that the two kinds of DGP ghosts are tightly correlated with each other, but are not always linked to the feature of selfacceleration. Our models are a promising laboratory for understanding the origins and physical meaning of braneworld ghosts, and perhaps for eliminating them altogether.
 Authors:
 Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, Illinois 60510 (United States)
 Department of Physics, University of California, Davis, California 95616 (United States)
 Publication Date:
 OSTI Identifier:
 21010951
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevD.75.026009; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ACCELERATION; BRANES; COSMOLOGY; GRAVITATION; GRAVITONS; MATHEMATICAL SOLUTIONS; NONLUMINOUS MATTER; QUANTUM FIELD THEORY; UNIVERSE
Citation Formats
Carena, Marcela, Lykken, Joseph, Santiago, Jose, and Park, Minjoon. Selfaccelerating warped braneworlds. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.026009.
Carena, Marcela, Lykken, Joseph, Santiago, Jose, & Park, Minjoon. Selfaccelerating warped braneworlds. United States. doi:10.1103/PHYSREVD.75.026009.
Carena, Marcela, Lykken, Joseph, Santiago, Jose, and Park, Minjoon. 2007.
"Selfaccelerating warped braneworlds". United States.
doi:10.1103/PHYSREVD.75.026009.
@article{osti_21010951,
title = {Selfaccelerating warped braneworlds},
author = {Carena, Marcela and Lykken, Joseph and Santiago, Jose and Park, Minjoon},
abstractNote = {Braneworld models with induced gravity have the potential to replace dark energy as the explanation for the current accelerating expansion of the Universe. The original model of Dvali, Gabadadze, and Porrati (DGP) demonstrated the existence of a 'selfaccelerating' branch of background solutions, but suffered from the presence of ghosts. We present a new large class of braneworld models which generalize the DGP model. Our models have negative curvature in the bulk, allow a second brane, and have general brane tensions and localized curvature terms. We exhibit three different kinds of ghosts, associated to the graviton zero mode, the radion, and the longitudinal components of massive graviton modes. The latter two species occur in the DGP model, for negative and positive brane tension, respectively. In our models, we find that the two kinds of DGP ghosts are tightly correlated with each other, but are not always linked to the feature of selfacceleration. Our models are a promising laboratory for understanding the origins and physical meaning of braneworld ghosts, and perhaps for eliminating them altogether.},
doi = {10.1103/PHYSREVD.75.026009},
journal = {Physical Review. D, Particles Fields},
number = 2,
volume = 75,
place = {United States},
year = 2007,
month = 1
}

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