Results 61 to 70 of about 4,095 (225)
A symmetric DBI action theory and its applications to inflationary cosmology
European Physical Journal C: Particles and Fields, 2021 The Dirac-Born-Infeld (DBI) field theory in string theory is important and can provide the field of the universe’s inflation. At the same time, it provides a causal mechanism for generating the original density perturbation, thereby providing the ...
Xiaokun Yang +2 more
doaj +1 more source
Journal of Geophysical Research: Space Physics, Volume 131, Issue 6, June 2026.Abstract A balloon borne Fabry Perot interferometer called High altitude Interferometer WIND observation (HIWIND) flew from Wanaka, New Zealand (44.69S, 169.14E) in April 2025 to observe mid‐latitude thermospheric winds in the southern hemisphere for the first time.
Qian Wu, Haonan Wu, Wenbin Wang
wiley +1 more source
Towards a cosmological dual to inflation
Physical Review D, 2011 We derive all single-field cosmologies with unit sound speed that generate scale invariant curvature perturbations on a dynamical attractor background. We identify three distinct phases: slow-roll inflation; a slowly contracting adiabatic ekpyrotic phase, described by a rapidly-varying equation of state; and a novel adiabatic ekpyrotic phase on a ...
Khoury, Justin, Miller, Godfrey E.J.
openaire +4 more sources
The fundamental arrow of time in classical cosmology [PDF]
, 2012 The aim of this paper is to show that a new understanding of fundamentality (section 2), can be applied successfully in classical cosmology and is able to improve a fundamental understanding of cosmological time asymmetries. In the introduction (section
Wohlfarth, Daniel
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Starobinsky-Like Inflation and Running Vacuum in the Context of Supergravity
Universe, 2016 We describe the primeval inflationary phase of the early Universe within a quantum field theoretical (QFT) framework that can be viewed as the effective action of vacuum decay in the early times. Interestingly enough, the model accounts for the “graceful
Spyros Basilakos +2 more
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New High Precision Measurements of Apollo Samples: 0.3–5 GHz Complex Refractive Indices
Journal of Geophysical Research: Planets, Volume 131, Issue 6, June 2026.Abstract Active and passive radar techniques provide information on the subsurface structure and history of planetary bodies. However, interpretations of radar data are limited by our understanding of the complex dielectric permittivity and magnetic permeability of the surface material.
P. Linton +15 more
wiley +1 more source
Confronting mukhanov parametrization of inflationary equation-of-State with ACT-DR6
Nuclear Physics BWe provide a simple yet effective semi-analytical approach to confront Mukhanov Parametrization of inflationary equation-of-state, 1+ω=β(N+1)α, with the latest ACT-DR6 data employing Hamilton-Jacobi formulation.
Barun Kumar Pal
doaj +1 more source
The Journal of Latin American and Caribbean Anthropology, Volume 31, Issue 2, June 2026.ABSTRACT This article examines the historical displacement of Indigenous peoples in Venezuela, focusing on the links between indigenist policies and the exploitation of natural resources, particularly oil, throughout the 20th century. Using a combined historical and ethnographic approach, it demonstrates how the formation of the Venezuelan nation‐state
Gabriel Tardelli
wiley +1 more source
Cosmology without inflation [PDF]
Physical Review D, 2008 We propose a new cosmological paradigm in which our observed expanding phase is originated from an initially large contracting Universe that subsequently experienced a bounce. This category of models, being geodesically complete, is non-singular and horizon-free, and can be made to prevent any relevant scale to ever have been smaller than the Planck ...
Peter, Patrick, Pinto-Neto, Nelson
openaire +3 more sources
braneworld cosmology and holography [PDF]
, 2002 This thesis is devoted to studying two important aspects of braneworld physics: their cosmology and their holography. We examine the Einstein equations induced on a general (n - 2)-brane of arbitrary tension, embedded in some n-dimensional bulk.
Padilla, Antonio
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