Slow-roll corrections to inflaton fluctuations on a brane

被引:14
作者
Koyama, K [1 ]
Mizuno, S
Wands, D
机构
[1] Univ Portsmouth, Inst Cosmol & Gravitat, Portsmouth PO1 2EG, Hants, England
[2] Waseda Univ, Dept Phys, Shinjuku Ku, Tokyo 1698555, Japan
来源
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS | 2005年 / 08期
关键词
cosmology with extra dimensions; cosmological perturbation theory; inflation;
D O I
10.1088/1475-7516/2005/08/009
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
Quantum fluctuations of an inflaton field, slow rolling during inflation are coupled to metric fluctuations. In conventional four-dimensional cosmology one can calculate the effect of scalar metric perturbations as slowroll corrections to the evolution of a massless free field in de Sitter spacetime. This gives the well-known first-order corrections to the field perturbations after horizon exit. If inflaton fluctuations on a four-dimensional brane embedded in a five-dimensional bulk spacetime are studied to first order in slow roll, then we recover the usual conserved curvature perturbation on superhorizon scales. But on small scales, at high energies, we find that the coupling to the bulk metric perturbations cannot be neglected, leading to a modified amplitude of vacuum oscillations on small scales. This is a large effect which casts doubt on the reliability of the usual calculation of inflaton fluctuations on the brane neglecting their gravitational coupling.
引用
收藏
页码:153 / 175
页数:23
相关论文
共 34 条
[1]   Brane cosmological evolution in a bulk with cosmological constant [J].
Binétruy, P ;
Deffayet, C ;
Ellwanger, U ;
Langlois, D .
PHYSICS LETTERS B, 2000, 477 (1-3) :285-291
[2]  
Calcagni G, 2003, J COSMOL ASTROPART P
[3]   Degeneracy of consistency equations in braneworld inflation [J].
Calcagni, G .
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS, 2004, (06) :15-30
[4]   Steep inflation: Ending braneworld inflation by gravitational particle production [J].
Copeland, EJ ;
Liddle, AR ;
Lidsey, JE .
PHYSICAL REVIEW D, 2001, 64 (02)
[5]  
COPELAND EJ, 2005, HEPPH0505149
[6]   On brane world cosmological perturbations [J].
Deffayet, C .
PHYSICAL REVIEW D, 2002, 66 (10)
[7]   Gravity in the Randall-Sundrum brane world [J].
Garriga, J ;
Tanaka, T .
PHYSICAL REVIEW LETTERS, 2000, 84 (13) :2778-2781
[8]  
GEORGE A, 2004, HEPTH0412067
[9]   INFLATIONARY UNIVERSE - A POSSIBLE SOLUTION TO THE HORIZON AND FLATNESS PROBLEMS [J].
GUTH, AH .
PHYSICAL REVIEW D, 1981, 23 (02) :347-356
[10]  
HIRAMATSU T, 2005, IN PRESS