A new covariant foliation-based construction of scalar-tensor theories up to four derivatives of the scalar field that extends DHOST and U-DHOST without unitary gauge and propagates three degrees of freedom.
Perturbations in k-inflation
6 Pith papers cite this work. Polarity classification is still indexing.
6
Pith papers citing it
abstract
We extend the theory of cosmological perturbations to the case when the ``matter'' Lagrangian is an arbitrary function of the scalar field and its first derivatives. In particular, this extension provides a unified description of known cases such as the usual scalar field and the hydrodynamical perfect fluid. In addition, it applies to the recently proposed k-inflation, which is driven by non-minimal kinetic terms in the Lagrangian. The spectrum of quantum fluctuations for slow-roll and power law k-inflation is calculated. We find, for instance, that the usual ``consistency relation'' between the tensor spectral index and the relative amplitude of scalar and tensor perturbations is modified. Thus, at least in principle, k-inflation is phenomenologically distinguishable from standard inflation.
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representative citing papers
Derives the elastic two-body unitarity relation for anisotropic scalar fields with different sound speeds, verifies it at one loop in a quartic model, and shows anisotropy modifies the radiatively generated scalon mass while leaving the Gildener-Weinberg flat direction unchanged.
K-inflation with non-canonical kinetic term G(φ) shifts α-attractor T-models and natural inflation into the Planck-ACT-LB-BK18 allowed region while satisfying Swampland conjectures and producing testable GW spectra.
Generalizes the interacting dilatonic ghost condensate dark energy model, performs phase-space analysis for non-interacting and two interacting cases, and reports parameter constraints from Cosmic Chronometers, PantheonPlus, and DESI data for n=3 and n=5.
A review thesis covering Mukhanov parametrization, general scalar-tensor theories, and new slow-roll techniques for canonical and noncanonical inflation observables.
A review that unifies analytical expressions for scalar-induced gravitational waves and emphasizes calculations for non-radiation-dominated cosmologies.
citing papers explorer
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Covariant scalar-tensor theories beyond second derivatives
A new covariant foliation-based construction of scalar-tensor theories up to four derivatives of the scalar field that extends DHOST and U-DHOST without unitary gauge and propagates three degrees of freedom.
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Disparity in sound speeds: implications for elastic unitarity and the effective potential in quantum field theory theory
Derives the elastic two-body unitarity relation for anisotropic scalar fields with different sound speeds, verifies it at one loop in a quartic model, and shows anisotropy modifies the radiatively generated scalon mass while leaving the Gildener-Weinberg flat direction unchanged.
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Reviving Motivated Inflationary Potentials with $K$-inflation in the light of ACT
K-inflation with non-canonical kinetic term G(φ) shifts α-attractor T-models and natural inflation into the Planck-ACT-LB-BK18 allowed region while satisfying Swampland conjectures and producing testable GW spectra.
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Generalizing the interacting dilatonic ghost condensate as a dark energy model
Generalizes the interacting dilatonic ghost condensate dark energy model, performs phase-space analysis for non-interacting and two interacting cases, and reports parameter constraints from Cosmic Chronometers, PantheonPlus, and DESI data for n=3 and n=5.
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Noncanonical Approaches To Inflation
A review thesis covering Mukhanov parametrization, general scalar-tensor theories, and new slow-roll techniques for canonical and noncanonical inflation observables.
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Scalar induced gravitational waves review
A review that unifies analytical expressions for scalar-induced gravitational waves and emphasizes calculations for non-radiation-dominated cosmologies.