In this paper, we review in detail different mechanisms of generation of large primordial
fluctuations and their implications for the production of primordial black holes (PBHs) and …

We construct a viable model of the vector coherent oscillation dark matter. The vector boson
is coupled to the inflaton through the kinetic function so that the effective Hubble mass term …

We study how Abelian-gauge-field production during inflation affects scalar perturbations in
the case when the gauge field interacts with the inflaton directly (by means of generic kinetic …

In the model of solid/elastic inflation, inflation is driven by a source that has the field
theoretical description of a solid. To allow for prolonged slow roll inflation, the solid needs to …

We study constant-roll inflation in the presence of a gauge field coupled to an inflaton. By
imposing the constant anisotropy condition, we find new exact anisotropic constant-roll …

Inflationary models can correlate small-scale density perturbations with the long-wavelength
gravitational waves (GW) in the form of the Tensor-Scalar-Scalar (TSS) bispectrum. This …

The presence of a light vector field coupled to a scalar field during inflation makes a distinct
prediction: the observed correlation functions of the cosmic microwave background (CMB) …

It is known that power-law k-inflation can be realized for the Lagrangian P= X g (Y), where
X=-(∂ ϕ) 2/2 is the kinetic energy of a scalar field ϕ and g is an arbitrary function in terms of …

We study inflation with anisotropic hair induced by form fields. In four dimensions, the
relevant form fields are gauge (one-form) fields and two-form fields. Assuming the …

Many models of inflation driven by vector fields alone have been known to be plagued by
pathological behaviors, namely ghost and/or gradient instabilities. In this work, we seek a …