Inflation with a stringy minimal length, reworked

Oct, 2008
17 pages
Published in:
  • JHEP 04 (2009) 005
e-Print:
Report number:
  • HU-EP-08-45

Citations per year

20092012201520182021102
Abstract: (arXiv)
In this paper we revisit the formulation of scalar field theories on de Sitter backgrounds subject to the generalized uncertainty principle (GUP). The GUP arises in several contexts in string theory, but is most readily thought of as resulting from using strings as effective probes of geometry, which suggests an uncertainty relation incorporating the string scale lsl_s. After reviewing the string theoretic case for the GUP, which implies a minimum length scale lsl_s, we follow in the footsteps of Kempf and concern ourselves as to how one might write down field theories which respect the GUP. We uncover a new representation of the GUP, which unlike previous studies, readily permits analytical solutions for the mode functions of a scalar field on de Sitter backgrounds. We find that scalar fields cannot be quantized on inflationary backgrounds with a Hubble radius H1H^{-1} smaller than the string scale, implying a potential sub-planckian cutoff on the scale of inflation resulting from the GUP. We also compute order (Hls)2(H l_s)^2 (as opposed to (Hlpl)2(H l_{pl})^2) corrections to the two point correlation function and comment on the future prospects of observing such corrections in the event our universe is described by a weakly coupled string theory.
  • inflation
  • generalized uncertainty principle
  • field theory: scalar
  • background: de Sitter
  • scaling: length
  • string model
  • space-time: Robertson-Walker