DBI in the sky

By M. Alishahiha, E. Silverstein, David Tong. 2004

1,028 citations recorded by the source corpus.

We analyze the spectrum of density perturbations generated in models of the recently discovered ''D-cceleration'' mechanism of inflation. In this scenario, strong coupling quantum field theoretic effects sum to provide a DBI-like action for the inflaton. We show that the model has a strict lower bound on the non-Gaussianity of the CMBR power spectrum at an observable level, and is thus falsifiable. This in particular observationally distinguishes this mechanism from traditional slow roll inflation generated by weakly interacting scalar fields. The model also favors a large observable tensor component to the CMBR spectrum.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/874caadd6fb24c04da1801aff515eb0ae0b0b386

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Citations in the corpus

Towards strange metallic holography (2009, background): “powers of γ, leading to strong non-Gaussian effects [29].”
Algorithms for bispectra: Forecasting, optimal analysis, and simulation (2006, background): “Next, we consider the ‘higher derivative model’ from Babich et al. (2004), which arises from adding the higher derivative operator (∇φ)4/(8 4) to the inflationary Lagrangian (Creminelli 2003; Alishahiha et al. 2004).”
Galileon inflation (2010, background): “However, when large nonlinearities are associated with the self-interactions of π there exists a decoupling limit in which reliable predictions can be extracted while neglecting gravity [4, 43, 50, 51].”
Planck 2015 results. XVII. Constraints on primordial non-Gaussianity (2015, positive): “DBI inflationary models based on string theory (Silverstein & Tong 2004; Alishahiha et al. 2004) provide physically well-motivated examples of the P(X, φ)-model.”
On the consistency relation of the three-point function in single-field inflation (2007, methodology): “Integrating out these modes induces a frictional force encapsulated by the low energy Lagrangian [3] SDBI = ∫”
FIVE-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE OBSERVATIONS: COSMOLOGICAL INTERPRETATION (2008, neutral): “Such models can be realized in the context of String Theory via the non-canonical kinetic action called the Dirac-Born-Infeld (DBI) form (Alishahiha et al. 2004), and in the context of an infrared modification of gravity called the ghost condensation (Arkani-Hamed et al. 2004).”
The bispectrum of galaxies from high-redshift galaxy surveys: Primordial non-Gaussianity and non-linear galaxy bias (2007, methodology): “A fNL with a peculiar scale dependence unrelated to the power spectrum appears, for instance, in string-motivated models such as DBI inflation (Alishahiha et al. 2004; Chen 2005).”
The dS/dS Correspondence (2004, background): “These two phenomena are holographically dual, as studied recently for zero temperature horizons in [18,15,16].”
Monodromy in the CMB: Gravity Waves and String Inflation (2008, background): “ [4]; the present mechanism and [36] are what emerged thus far from this study. Similar comments apply to other corners of ﬁeld theory and string theory with predictive inﬂationary signatures such as [27, 38, 39, 40]. The development of a detailed understanding of UV complete cosmological solutions ”