Initial state effects on the cosmic microwave background and trans-Planckian physics

2002/08/31 by Kevin Goldstein, David A. Lowe · 8 citations
Physics and Astronomy · #Cosmology and Gravitation Theories #Noncommutative and Quantum Gravity Theories #Quantum Electrodynamics and Casimir Effect #astro-ph #gr-qc #hep-th

paper · pdf · doi:10.1103/physrevd.67.063502

published as Phys.Rev. D67 (2003) 063502 · 10 pages, harvmac, references added, expanded discussion

arxiv created 2002/09/02 · openalex publication_date 2003/03/13 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

There exists a one complex parameter family of de Sitter invariant vacua, known as \ensuremathα vacua. In the context of slow roll inflation, we show that all but the Bunch-Davies vacuum generates unacceptable production of high energy particles at the end of inflation. As a simple model for the effects of trans-Planckian physics, we go on to consider non--de Sitter invariant vacua obtained by patching modes in the Bunch-Davies vacuum above some momentum scale M_c, with modes in an \ensuremathα vacuum below M_c. Choosing M_c near the Planck scale M_Pl, we find acceptable levels of hard particle production, and corrections to the cosmic microwave perturbations at the level of HM_Pl/M_c², where H is the Hubble parameter during inflation. More general initial states of this type with H\ensuremath≪M_c\ensuremath≪M_Pl can give corrections to the spectrum of cosmic microwave background perturbations at order 1. The parameter characterizing the \ensuremathα vacuum during inflation is a new cosmological observable.

Citations

• Minimal modifications of the primordial power spectrum from an adiabatic short distance cutoff

Cited by

• A note on α-vacua and interacting field theory in de Sitter space
• α-states in de Sitter space
• Temperature effect on the power spectrum in inflation
• Renormalization of initial conditions and the trans-Planckian problem of inflation
• The renormalization of the energy-momentum tensor for an effective initial state
• Vacuum choices and the predictions of inflation
• Quantum stress tensor fluctuations of a conformal field and inflationary cosmology
• Real-time perturbation theory in de Sitter space