Related papers: Curvaton Dynamics Revisited
We discuss the damping of primordial dark matter fluctuations, taking into account explicitly the interactions of dark matter - whatever their intensity - both with itself and with other particle species. Relying on a general classification…
We argue that the curvaton decay takes place most naturally by way of a broad parametric resonance. The mechanism is analogous to resonant inflaton decay but does not require any tuning of the curvaton coupling strength to other scalar…
Primordial non-Gaussianity signatures of extremely heavy particles are re-examined within a simple alternative to the standard inflationary paradigm, in which the primordial fluctuations and the inflationary spacetime expansion are sourced…
Turbulent plasma flow, amplified by rapid 3D compression, can be suddenly dissipated under continuing compression. This effect relies on the sensitivity of the plasma viscosity to the temperature, $\mu \sim T^{5/2}$. The plasma viscosity is…
Decay in time of undriven weakly collisional kinetic plasma turbulence in systems large compared to the ion kinetic scales is investigated using fully electromagnetic particle-in-cell simulations initiated with transverse flow and magnetic…
A specific set of dimensionless plasma and turbulence parameters is introduced to characterize the nature of turbulence and its dissipation in weakly collisional space and astrophysical plasmas. Key considerations are discussed for the…
We discuss the potentially important role played by preheating in certain variants of the curvaton mechanism in which isocurvature perturbations of a D-flat (and F-flat) direction become converted to curvature perturbations during…
In this Letter, we use a model fluid mechanics experiment to elucidate the impact of curvature heterogeneities on two-dimensional fields deriving from harmonic potential functions. This result is directly relevant to explain the smooth…
Thermal instability in an electron-ion magnetized plasma, which is relevant in the intragalactic medium (IGM) of galaxy clusters, solar corona, and other two-component plasma objects is investigated. We apply the multicomponent plasma…
In this paper, we will use $\delta \mathcal{N}$-formalism to calculate the primordial curvature perturbation for the curvaton model with a Lagrange multiplier field. We calculate the non-linearity parameters $f_{NL}$ and $g_{NL}$ in the…
The evolution of the curvature perturbation after multi-field inflation is studied in the light of the curvaton mechanism. Past numerical studies show that many-field inflation causes significant evolution of the curvature perturbation…
We investigate thermal instability in an electron-ion magnetized plasma relevant to galaxy clusters, solar corona, and other two-component astrophysical objects. We apply the multicomponent plasma approach when the dynamics of all the…
A curvature self-interaction of the cosmic gas is shown to mimic a cosmological constant or other forms of dark energy, such as a rolling tachyon condensate or a Chaplygin gas. Any given Hubble rate and deceleration parameter can be traced…
We discuss two possible scenarios, namely the curvaton mechanism and the dark matter density modulation, where non-Gaussianity signals of superheavy dark matter produced by gravity can be enhanced and observed. In both scenarios, superheavy…
Via numerical simulations and analytical calculations, depletion forces are studied in mixtures of small and big particles that interact via soft repulsive potentials. While big particles are spherical, small particles are nonspherical with…
We consider the possibility of suppressing superhorizon curvature perturbations after the end of the ordinary slow-roll inflationary stage. This is the opposite of the curvaton limit. We assume that large curvature perturbations are created…
We investigate the curvaton dynamics and the non-linearity parameters in curvaton model with potential slightly deviating from the quadratic form in detail. The non-linearity parameter $g_{NL}$ will show up due to the curvaton…
Motivated by the fact that a sharply peaked curvature spectrum is often considered in the literature, we examine theoretical constraints on the sharpness of such a spectrum. In particular, we show that the sharply peaked curvature power…
Thermal fluctuations strongly modify the large length-scale elastic behavior of crosslinked membranes, giving rise to scale-dependent elastic moduli. While thermal effects in flat membranes are well understood, many natural and artificial…
The mimetic gravity theory is one of the interesting modified gravity theories, which aims to unify the matter component of our universe within the power of gravity. The mimetic-like theory can also be responsible for primordial…