Search arXiv⌕ Search
Home/Archive/arXiv

arXiv · 1502.05166

Non-local scalar fields inflationary mechanism in light of Planck $2013$

Haidar Sheikhahmadi·Soheyla Ghorbani·Khaled Saaidi
View original source ↗Read source document ↗Export metadata ↓

Abstract

A generalization of the canonical and non-canonical theory of inflation is introduced in which the kinetic energy term in action is written as non-local term. The inflationary universe within the framework of considering this non-locality will be studied. To investigate the effects of non-locality on the inflationary parameters we consider two well known models of inflationary scenario includes of chaotic and exponential inflation proposals. For such scenarios some important parameters include slow roll parameters, scalar and tensor power spectra, spectral indices, the tensor-to-scalar ratio and so on for both mentioned models, chaotic and exponential inflationary scenarios, will be calculated. Also the Hamilton-Jacobi formalism, as an easiest way to study the effect of perturbation based on e-folding number $N$, to investigate inflationary attractors will be used. The free theoretical parameters of this model will be compared with observations by means of Planck $2013$, $WMAP9+eCMB+BAO+H_0$ data sets in addition to $BICEP2$ data surveying. It will be shown that our theoretical results are in acceptable range in comparison to observations. For instance the tensor-to-scalar ratio for exponential potential, by considering $BICEP2$ is in best agreement in comparison with chaotic inflation.

Explore related subjects

gr-qc

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Haidar Sheikhahmadi, Soheyla Ghorbani, Khaled Saaidi. 2015-02-18. Non-local scalar fields inflationary mechanism in light of Planck $2013$. https://doi.org/10.1007/s10509-015-2343-2

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Quantum Correlations of Neutrinos in the Kerr-Newman Space-time

Quantum phases establish a connection between gravitation and quantum information, offering a novel avenue for exploring the properties of space-time. In this paper, we investigate the quantum correlations (QCs) of neutrinos in the Kerr--Newman space-time for both zero- and nonzero-angular-momentum propagation. The results show that, for zero-angular-momentum propagation, the oscillation periods of the survival probability and QCs progressively decrease with propagation distance in the inward direction. In the outward direction, increasing $M$ lengthens the oscillation periods of $P_{ν_e\rightarrowν_e}$, entanglement, and the monogamy of nonlocality, whereas increasing the angular momentum $a$ or charge $Q$ shortens them. For nonzero-angular-momentum propagation, the metric parameters also generate local profile modulations through additional two-path interference terms, rather than merely rescaling the oscillation period. Furthermore, we find that, despite differences in their ranges of variation, entanglement and coherence exhibit highly consistent oscillatory behavior in both propagation cases. These findings provide a comprehensive understanding of neutrino-based relativistic quantum information.

gr-qc↗
arXiv2026

Tidal Love numbers of wormholes as black-hole mimickers

We study the dynamical scalar tidal Love numbers of wormholes that provide viable mimickers for black holes, focusing on thin-shell Schwarzschild and Damour-Solodukhin geometries. Using a matched near- and far-zone expansion, we determine their tidal response in the low-frequency regime. The presence of a long throat introduces an additional characteristic scale and naturally separates the modes into two classes. Super-throat modes probe the global wormhole geometry and are sensitive to both asymptotic regions, whereas sub-throat modes probe only one side of the wormhole and effectively perceive the throat as a black-hole horizon. We derive the scalar tidal Love numbers analytically for both classes of modes and show that their dissipative parts exhibit distinct low-frequency behavior, reflecting whether one or both potential barriers participate in the scattering process. We further find that, as the wormhole approaches the black-hole limit, the super-throat contribution becomes progressively negligible, while the sub-throat response smoothly reduces to that of a Schwarzschild black hole. These results demonstrate that the tidal response of wormholes depends crucially on whether the perturbation probes the global structure of the throat.

gr-qc↗
arXiv2026

Effective Matter Conversion in Gravitational Collapse and the Dynamical Formation of Regular Black Holes

We study inverse source reconstruction in generalized Vaidya spacetimes. A prescribed density fixes the mass and tangential pressure, while a two-sector decomposition determines a dimensionless radial balance function. We distinguish this function from a time-directed conversion rate and identify the additional null-flux information required for a covariant exchange vector. Positivity restricts the allowed target pressures: a de Sitter core cannot be represented by nonnegative sectors with nonnegative tangential equations of state. An explicit finite-density profile admits a positive vacuum-like completion, finite curvature invariants, and inner and outer trapping horizons above a calculable threshold. Its total source satisfies the null, weak, and dominant energy conditions during monotonic accretion, while the timelike convergence condition fails in the core. We check polytropic, bag-model-inspired, and condensate-inspired profiles and the corresponding cosmological reconstruction. Finally, we compute the stationary endpoint's shadow and compare its exterior deformation with published Sagittarius A* measurements. The construction establishes local curvature regularity and marginal-sphere formation, without claiming a microscopic formation mechanism, perturbative stability, or geodesic completeness.

gr-qc↗