Correlators of vector, tensor, and scalar composite vertices of order O($$ {\alpha}_{\mathrm{s}}^2 $$β0)
Sign Up to like & getrecommendations! Published in 2021 at "Journal of High Energy Physics"
DOI: 10.1007/jhep02(2021)197
Abstract: Abstract We present analytical results for massless correlators of two vector, tensor, and scalar composite vertices with the Bjorken fractions x and y of order $$ {\alpha}_s^2 $$ α s 2 β0 of QCD. The… read more here.
Keywords: order alpha; composite vertices; vector tensor; scalar composite ... See more keywords
CMB bounds on tensor-scalar-scalar inflationary correlations
Sign Up to like & getrecommendations! Published in 2017 at "Journal of Cosmology and Astroparticle Physics"
DOI: 10.1088/1475-7516/2018/01/016
Abstract: The nonlinear interaction between one graviton and two scalars is enhanced in specific inflationary models, potentially leading to distinguishable signatures in the bispectrum of the cosmic microwave background (CMB) anisotropies. We develop the tools to… read more here.
Keywords: tensor scalar; inflationary correlations; scalar scalar; cmb bounds ... See more keywords
Non-Gaussianity beyond the scalar sector: A search for tensor and mixed tensor-scalar bispectra with Planck data
Sign Up to like & getrecommendations! Published in 2024 at "Physical Review D"
DOI: 10.1103/pb7x-lp19
Abstract: Primordial gravitational waves could be non-Gaussian, just like primordial scalar perturbations. Although the tensor two-point function has thus-far remained elusive, the three-point function could, in principle, be large enough to be detected in Cosmic Microwave… read more here.
Keywords: tensor; non gaussianity; mixed tensor; tensor scalar ... See more keywords
Small field models of inflation that predict a tensor-to-scalar ratio r=0.03
Sign Up to like & getrecommendations! Published in 2019 at "Physical Review D"
DOI: 10.1103/physrevd.100.043522
Abstract: Future observations of the cosmic microwave background (CMB) polarization are expected to set an improved upper bound on the tensor-to-scalar ratio of $r\lesssim 0.03$. Recently, we showed that small field models of inflation can produce… read more here.
Keywords: field; scalar ratio; models inflation; field models ... See more keywords
Natural inflation with exponentially small tensor-to-scalar ratio
Sign Up to like & getrecommendations! Published in 2024 at "Physical Review D"
DOI: 10.1103/physrevd.110.l061302
Abstract: We demonstrate that"natural inflation", also known as"axion inflation", can be compatible with Planck 2018 measurements of the cosmic microwave background, while predicting an exponentially small tensor-to-scalar ratio, e.g., $r\sim 10^{-15}$. The strong suppression of $r$… read more here.
Keywords: scalar ratio; inflation; natural inflation; tensor scalar ... See more keywords
How to produce an arbitrarily small tensor to scalar ratio
Sign Up to like & getrecommendations! Published in 2019 at "Modern Physics Letters A"
DOI: 10.1142/s0217732319501311
Abstract: In this paper, construct a toy a model which demonstrates that large field single scalar inflation can produce an arbitrarily small scalar to tensor ratio in the window of e-foldings recoverable from CMB experiments. This… read more here.
Keywords: ratio; produce arbitrarily; arbitrarily small; small tensor ... See more keywords
Effective Gravitational “Constant” in Scalar-(Curvature)Tensor and Scalar-Torsion Gravities
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DOI: 10.3390/universe3020037
Abstract: In theories where a scalar field couples nonminimally to gravity, the effective gravitational “constant” becomes dependent on the value of the scalar field. This note first gives a brief review on how the cosmological evolution… read more here.
Keywords: tensor scalar; gravitational constant; tensor; effective gravitational ... See more keywords
Gauss–Bonnet Inflation and the String Swampland
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DOI: 10.3390/universe5090200
Abstract: The swampland criteria are generically in tension with single-field slow-roll inflation because the first swampland criterion requires small tensor-to-scalar ratio while the second swampland criterion requires either large tensor-to-scalar ratio or large scalar spectral tilt.… read more here.
Keywords: swampland; tensor scalar; gauss bonnet; slow roll ... See more keywords