Density perturbations and the cosmological constant from inflationary landscapes

被引:51
作者
Feldstein, B [1 ]
Hall, LJ
Watari, T
机构
[1] Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA
[2] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA
关键词
D O I
10.1103/PhysRevD.72.123506
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
An anthropic understanding of the cosmological constant requires that the vacuum energy at late time scans from one patch of the universe to another. If the vacuum energy during inflation also scans, the various patches of the universe acquire exponentially differing volumes. In a generic landscape with slow-roll inflation, we find that this gives a steeply varying probability distribution for the normalization of the primordial density perturbations, resulting in an exponentially small fraction of observers measuring the Cosmic Background Explorer value of 10(-5). Inflationary landscapes should avoid this "sigma problem," and we explore features that can allow them to do that. One possibility is that, prior to slow-roll inflation, the probability distribution for vacua is extremely sharply peaked, selecting essentially a single anthropically allowed vacuum. Such a selection could occur in theories of eternal inflation. A second possibility is that the inflationary landscape has a special property: although scanning leads to patches with volumes that differ exponentially, the value of the density perturbation does not vary under this scanning. This second case is preferred over the first, partly because a flat inflaton potential can result from anthropic selection, and partly because the anthropic selection of a small cosmological constant is more successful.
引用
收藏
页数:12
相关论文
共 64 条
[1]  
Acharya BS, 2005, J HIGH ENERGY PHYS
[2]   Cold big-bang cosmology as a counterexample to several anthropic arguments [J].
Aguirre, A .
PHYSICAL REVIEW D, 2001, 64 (08)
[3]  
[Anonymous], HEPTH0501082
[4]  
Arkani-Hamed N, 2003, J COSMOL ASTROPART P
[5]  
Ashok SK, 2004, J HIGH ENERGY PHYS
[6]  
Banks T, 2004, J HIGH ENERGY PHYS
[7]   ZERO COSMOLOGICAL CONSTANT FROM MINIMUM ACTION [J].
BAUM, E .
PHYSICS LETTERS B, 1983, 133 (3-4) :185-186
[8]   Loop corrections to volume moduli and inflation in string theory -: art. no. 026005 [J].
Berg, M ;
Haack, M ;
Körs, B .
PHYSICAL REVIEW D, 2005, 71 (02) :026005-1
[9]   Quantization of four-form fluxes and dynamical neutralization of the cosmological constant [J].
Bousso, R ;
Polchinski, J .
JOURNAL OF HIGH ENERGY PHYSICS, 2000, (06) :1-25
[10]   FATE OF FALSE VACUUM .2. 1ST QUANTUM CORRECTIONS [J].
CALLAN, CG ;
COLEMAN, S .
PHYSICAL REVIEW D, 1977, 16 (06) :1762-1768