DBI Galileon inflation in the light of Planck 2015

Journal Article · Mon Feb 01 04:00:00 EST 2016 · Journal of Cosmology and Astroparticle Physics

DOI:https://doi.org/10.1088/1475-7516/2016/02/063· OSTI ID:22524975

Kumar, K. Sravan; Marto, J.; Moniz, P. Vargas ^[1]; Sánchez, Juan C. Bueno ^[2]; Escamilla-Rivera, Celia ^[3]

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1. Departamento de Física, Universidade da Beira Interior (UBI), Covilhã, 6200 Portugal (Portugal)
2. Departamento de Física, Universidad del Valle, Ciudadela Universitaria Melendez, Calle 13 No. 100-00, Santiago de Cali, A.A. 25360 Colombia (Colombia)
3. Departamento de Física, Universidade Federal do Espírito Santo, Av. Fernando Ferrari 514, Vitória, ES, 29075-910 Brazil (Brazil)

In this work we consider a DBI Galileon (DBIG) inflationary model and constrain its parameter space with the Planck 2015 and BICEP2/Keck array and Planck (BKP) joint analysis data by means of a potential independent analysis. We focus our attention on inflationary solutions characterized by a constant or varying sound speed as well as warp factor. We impose bounds on stringy aspects of the model, such as the warp factor (f) and the induced gravity parameter ( m-tilde ). We study the parameter space of the model and find that the tensor-to-scalar ratio can be as low as r ≅ 6 × 10{sup −4} and inflation happens to be at GUT scale. In addition, we obtain the tilt of the tensor power spectrum and test the standard inflationary consistency relation (r = −8n{sub t}) against the latest bounds from the combined results of BKP+Laser Interferometer Gravitational-Waves Observatory (LIGO), and find that DBIG inflation predicts a red spectral index for the tensor power spectrum.

• OSTI ID: 22524975
• Journal Information: Journal of Cosmology and Astroparticle Physics, Journal Name: Journal of Cosmology and Astroparticle Physics Journal Issue: 02 Vol. 2016; ISSN 1475-7516
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
BORN-INFELD THEORY
COSMOLOGICAL INFLATION
ENERGY SPECTRA
GRAVITATIONAL WAVES
INDEXES
INFLATIONARY UNIVERSE
MATHEMATICAL SOLUTIONS
POTENTIALS
SCALARS
SOUND WAVES
SPACE
TENSORS
VELOCITY
VISIBLE RADIATION