We present a new realization of the resonant production primordial black holes as well gravitational waves in two-stage inflation model consisting scalar field ϕwith an axion-monodromy-like periodic structure potential that governs first stage and another χwith hilltop-like dominates second stage. The parametric resonance seeded by at amplifies perturbations both fields inside Hubble radius. While evolution background trajectory experiences turn oscillatory barrier height increases,...

Abstract Gravitational waves offer a potent mean to test the underlying theory of gravity. In general theories gravity, such as scalar-tensor theories, one expects modifications in friction term and sound speed gravitational wave equation. that case, rapid oscillations coefficients, e.g. due an oscillating scalar field, may lead narrow parametric resonances strain. We perform analysis possibility within DHOST theories. use disformal transformations find space with larger resonances,...

Structural anisotropy in layered two-dimensional materials can lead to highly anisotropic optical absorption which, turn, profoundly a^ect their phonon modes. These e^ects include lattice orientation-dependent and excitation energy-dependent mode intensities that enable new phononic optoelectronic applications. Here, we report anomalous Raman spectra single-crystalline AgCrP$_2$Se$_6$, a antiferromagnetic material. Density functional theory calculations experimental measurements reveal...

Abstract In this study, we generalize the Fokker-Planck equation to two-dimensional cases, including potential functions with periodic boundary conditions and piecewise-defined structures, analyze probability distribution in multi-field inflationary models. We employ spectral method for spatial derivatives Crank-Nicolson time evolution solve numerically slow-roll inflation. find that was determined by combined parameters. And volume weighting effect makes Volume is potential.

In light of the non-perturbative resonance effects that may occur during inflation, we introduce a parametrization for power spectrum stochastic gravitational wave background (SGWB) characterized by narrow-band amplification. We utilize universal $\Omega_\text{GW}\propto k^3$ infrared limit, applicable to wide array sources, devise robust yet straightforward parameterization optimized Markov Chain Monte Carlo (MCMC) analyses. This is demonstrated through select examples where its application...

During inflationary preheating, the energy stored in inflaton field is rapidly converted into excitations of other entropy fields. This stage characterized by exponential particle production due to parametric resonance and notoriously difficult analyze using analytic methods. We develop a detailed numerical simulation investigate preheating when potential power-law function with arbitrary power index. To achieve successful graceful exit from primordial phase smooth, oscillatory during we...

In this paper, a simple and effective attack on non-blind robust digital watermark method, cocktail watermarking, was proposed. After reviewing the principle of paper discovered that watermarking scheme can drive very high false positive probability although with robustness simultaneously. Furthermore, counterfeiting to generate watermarked image an original proposed, which pass through extraction authentication successfully in case none embedded. This demonstrates algorithm is flawed be...

Abstract We present the first lattice simulation to investigate nature of multi-stream inflation. The confirms physical picture inflation, and with new findings in parameter space field behaviors. Our shows that gradient energy plays a significant role For double potential shifted Gaussian barrier, bifurcation probability is controlled by shift distance an error function relation. bubbles created tend be more spherical as decreases. Also, likely introduce oscillations values inside than outside.

We propose a novel mechanism for enhancing primordial gravitational waves without significantly affecting the curvature perturbations produced during inflation. This is achieved due to nonlinear sourcing of resonantly amplified scalar field fluctuations. Our result an explicit scale-dependent counterexample famous Lyth bound, which opens up promising perspective producing detectable inflationary tensor modes with low-scale inflation and sub-Planckian excursion. explicitly demonstrate...

In light of the non-perturbative resonance effects that may occur during inflation, we introduce a parametrization for power spectrum stochastic gravitational wave background (SGWB) characterized by narrow-band amplification.We utilize universal Ω GW ∝ k 3 infrared limit, applicable to wide array sources, devise robust yet straightforward parameterization optimized Markov Chain Monte Carlo (MCMC) analyses.This is demonstrated through select examples where its application pertinent, and...

\texttt{PSpectCosmo} is a high-performance \texttt{C++} program developed to investigate early-universe cosmological dynamics, with specific emphasis on the inflationary epoch. Utilizing Fourier-space pseudo-spectral method, enables precise evolution of interacting scalar fields and gravitational waves, ensuring accurate representation power spectrum during inflation. This approach overcomes key limitations finite difference methods, particularly in maintaining consistency between effective...

Most cosmic microwave background experiments observe the sky along circular or near-circular scans on celestial sphere. For such experiments, we show that simple linear systems connect Fourier spectra of temperature and polarization time-ordered data to harmonic T, E B We also how this can be used estimate those directly from streams by inversion a system connects angular power spectra, offering an easy way down-weight modes observation most contaminated low-frequency noise, ground pickup,...

The following spectra of LiYF4:Nd have been observed for the first time: (i) electronic and electron-phonor Raman stark sub-levels Y1-Y6 energy levels 4I11/2 excited by 4880? Ar+ laser beam; (ii) two-photon fluorescence 6943? ruby beam.

As the number of application images on Internet increases, how to store and transmit these becomes a big challenge. JPEG as most widely used image compression format is often applied pictures compression. However, just using alone compress not enough now. In hence, some methods use improved entropy coding further recompress losslessly or process DCT domain for lossy recompression. These are useful work various images. But there no special design fixed surveillance applications. Depending...

The Sun's magnetic field is strongly structured over a broad range of scales. spatial power spectral analysis provides powerful tool to understand the various scales fields and their interaction with plasma motion. We aim investigate spectra using spherical harmonic decomposition high-resolution SOHO/MDI SDO/HMI synoptic magnetograms covering three consecutive solar cycle minima in series papers. As first series, we calibrate analyze based on co-temporal data this paper. For time, find that...

In this paper, a simple and effective attack on non-blind robust digital watermark method, cocktail watermarking, was proposed. After reviewing the principle of paper discovered that watermarking scheme can drive very high false positive probability although with robustness simultaneously. Furthermore, counterfeiting to generate watermarked image an original proposed, which pass through extraction authentication successfully in case none embedded. This demonstrates algorithm is flawed be...

This is the first theoretical calculation covering whole energy range in LaFa3Nd3+ by using a crystalfield Hamiltonian of C2 point symmetry. The rms deviation about 20.2 cm-2. Thus far, this most accurate one. We also correct previous assign ments some sub-levels.

Effects of anisotropy, symmetry, atom arrangement and Coulomb interaction on the linear optical polarizability spectra five C78 isomers are theoretically studied by using extended Su–Schrieffer–Heeger model with without interaction. The main results as follows. 1) become anisotropic respect to direction electric field light. property is common in niorlel 2) symmetry have grcat effects peak positions, strengths, number. 3) tends shift peaks higher energies enhances oscillator strengths at energies.