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New Inflation. Amy Bender 05/03/2006. Inflation Basics. Perturbations from quantum fluctuations of scalar field Fluctuations are: Gaussian Scale Invariant Spectrum (almost) k 3 P Φ (k) ~ constant Adiabatic Scalar & Tensor Matter/radiation anisotropies & gravity waves
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New Inflation Amy Bender 05/03/2006
Inflation Basics • Perturbations from quantum fluctuations of scalar field • Fluctuations are: • Gaussian • Scale Invariant Spectrum (almost) • k3PΦ(k) ~ constant • Adiabatic • Scalar & Tensor • Matter/radiation anisotropies & gravity waves • N > 50 - 60 e-foldings
3 Parameters • ns: Scalar spectral index • Scale free ns=1 • r: ratio of amplitude of tensor to scalar fluctuations (δH/AT) • dns/dlnk: running of scalar spectral index • WMAP 3 year data • ns ~ 0.951 ± 0.02 • r < 0.28 • dns/dlnk < 0
Single Field Inflation • Effective Lagrangian • Potential dominates KE • Evolution Equations (from energy momentum tensor & Friedmann Eqn) • Slow Roll Approximation • Inflation field & Hubble parameter vary slowly • Parameters in terms of derivatives of the potential
ω0=0 h=y=1 ω χ New Inflation Vega & Sanchez, astro-ph/0604136 • Quartic Trinomial Potential • y is coupling parameter, h is asymmetry parameter
Energy Scale of Inflation • Scalar perturbation amplitude • From WMAP: = 4.67 10-5 • With N=50, find M ~ 0.77 1016 GeV • GUT scale ~ 1016 GeV—physics?
Calculation of Parameters • From limits of y & h, can constrain cosmology • ns: limit on the maximum value • ns,max = 0.96 • r < 0.16 for all coupling parameters • dns/dlnk: depends on coupling (or other params) • WMAP ns = 0.95 • 0.03 < r < 0.04 • -0.00070 < dns/dlnk < -0.00055 • Consistent!!!
Other Scenarios • Hybrid Inflation • Inflation field is coupled to another scalar field • Chaotic Inflation • V(φ)=λφ4, initial ‘chaotic’ distribution of φ ≠ 0 • Future of New Inflation • Need to constrain r & running parameter better observationally • What does this mean for GUT theory?