TY - JOUR

T1 - Observational consequences of a landscape

AU - Freivogel, Ben

AU - Kleban, Matthew

AU - Martínez, María Rodríguez

AU - Susskind, Leonard

PY - 2006/3/1

Y1 - 2006/3/1

N2 - In this paper we consider the implications of the "landscape" paradigm [1], [2] for the large scale properties of the universe. The most direct implication of a rich landscape is that our local universe was born in a tunnelling event from a neighboring vacuum. This would imply that we live in an open FRW universe with negative spatial curvature. We argue that the "overshoot" problem, which in other settings would make it difficult to achieve slow roll inflation, actually favors such a cosmology. We consider anthropic bounds on the value of the curvature and on the parameters of inflation. When supplemented by statistical arguments these bounds suggest that the number of inflationary efolds is not very much larger than the observed lower bound. Although not statistically favored, the likelihood that the number of efolds is close to the bound set by observations is not negligible. The possible signatures of such a low number of efolds are briefly described.

AB - In this paper we consider the implications of the "landscape" paradigm [1], [2] for the large scale properties of the universe. The most direct implication of a rich landscape is that our local universe was born in a tunnelling event from a neighboring vacuum. This would imply that we live in an open FRW universe with negative spatial curvature. We argue that the "overshoot" problem, which in other settings would make it difficult to achieve slow roll inflation, actually favors such a cosmology. We consider anthropic bounds on the value of the curvature and on the parameters of inflation. When supplemented by statistical arguments these bounds suggest that the number of inflationary efolds is not very much larger than the observed lower bound. Although not statistically favored, the likelihood that the number of efolds is close to the bound set by observations is not negligible. The possible signatures of such a low number of efolds are briefly described.

KW - dS vacua in string theory

UR - http://www.scopus.com/inward/record.url?scp=33645656842&partnerID=8YFLogxK

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U2 - 10.1088/1126-6708/2006/03/039

DO - 10.1088/1126-6708/2006/03/039

M3 - Review article

AN - SCOPUS:33645656842

SP - 1005

EP - 1023

JO - Journal of High Energy Physics

JF - Journal of High Energy Physics

SN - 1126-6708

IS - 3

ER -