Rights statement: © 2006 The American Physical Society
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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Current acceleration from the dilaton and stringy cold dark matter
AU - Biswas, Tirthabir
AU - Brandenberger, Robert
AU - Mazumdar, Anupam
AU - Multamaki, Tuomas
N1 - © 2006 The American Physical Society 6 pages, 4 figures (colour)
PY - 2006/9/5
Y1 - 2006/9/5
N2 - We argue that string theory has all the ingredients to provide us with candidates for the cold dark matter and explain the current acceleration of our Universe. In any generic string compactification the dilaton plays an important role as it couples to the Standard Model and other heavy non-relativistic degrees of freedom such as the string winding modes and wrapped branes, we collectively call them stringy cold dark matter. These couplings are non-universal which results in an interesting dynamics for a rolling dilaton. Initially, its potential can track radiation and matter while beginning to dominate the dynamics recently, triggering a phase of acceleration. This scenario can be realized as long as the dilaton also couples strongly to some heavy modes. We furnish examples of such modes. We provide analytical and numerical results and compare them with the current supernovae result. This favors certain stringy candidates.
AB - We argue that string theory has all the ingredients to provide us with candidates for the cold dark matter and explain the current acceleration of our Universe. In any generic string compactification the dilaton plays an important role as it couples to the Standard Model and other heavy non-relativistic degrees of freedom such as the string winding modes and wrapped branes, we collectively call them stringy cold dark matter. These couplings are non-universal which results in an interesting dynamics for a rolling dilaton. Initially, its potential can track radiation and matter while beginning to dominate the dynamics recently, triggering a phase of acceleration. This scenario can be realized as long as the dilaton also couples strongly to some heavy modes. We furnish examples of such modes. We provide analytical and numerical results and compare them with the current supernovae result. This favors certain stringy candidates.
U2 - 10.1103/PhysRevD.74.063501
DO - 10.1103/PhysRevD.74.063501
M3 - Journal article
VL - 74
JO - Physical Review D
JF - Physical Review D
SN - 1550-7998
IS - 6
M1 - 063501
ER -