Results 101 to 110 of about 299,841 (224)
Viable inflationary models in a ghost-free Gauss–Bonnet theory of gravity
European Physical Journal C: Particles and Fields, 2019 In this work we investigate the inflationary phenomenological implications of a recently developed ghost-free Gauss–Bonnet theory of gravity. The resulting theory can be viewed as a scalar Einstein–Gauss–Bonnet theory of gravity, so by employing the ...
Shin’ichi Nojiri +4 more
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The Cosmological Perturbed Lightcone Gauge [PDF]
Universe, 2018 The lightcone gauge is a set of what are called the observational coordinates adapted to our past lightcone. We develop this gauge by producing a perturbed spacetime metric that describes the geometry of our past lightcone where observations are usually obtained. We connect the produced observational metric to the perturbed Friedmann-Lemaître-Robertson-
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InfoScience, Volume 3, Issue 3, September 2026.With the advancement of 6G communications, high‐precision radar, and advanced imaging technologies, there is a growing demand for compact, high‐performance light sources capable of generating high‐frequency radio waves (millimeter‐wave and terahertz waves). This article systematically introduces how to efficiently generate these high‐frequency waves on
Jianfeng Xiong +8 more
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Reheating in a modified teleparallel model of inflation
European Physical Journal C: Particles and Fields, 2019 We study the cosmological inflation and reheating in a teleparallel model of gravity. Reheating is assumed to be due to the decay of a scalar field to radiation during its rapid oscillation.
Parviz Goodarzi, H. Mohseni Sadjadi
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Journal of High Energy Physics, 2020 The quantum fluctuations of the Higgs field during inflation could be a source of primordial density perturbations through Higgs-dependent inflaton decay.
Shiyun Lu, Yi Wang, Zhong-Zhi Xianyu
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On brane world cosmological perturbations [PDF]
Physical Review D, 2002 36 pages, 1 ...
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Numerical Investigations of Low‐Latitude Ground Magnetic Fields Due To Cavity Mode Oscillations
Journal of Geophysical Research: Space Physics, Volume 131, Issue 9, September 2026.Abstract Pi2 oscillations are known to be associated with cavity mode oscillations (CMOs) in the inner magnetosphere at low latitudes. CMOs can also be excited by interplanetary shocks on the dayside. We present results from a global linear MHD wave model in spherical coordinates that allows us to analyze these waves at equatorial latitudes.
K. Majmudar, R. L. Lysak, K. Takahashi
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上海师范大学学报. 自然科学版, 2015 We study the cosmological inflation models driven by the rolling tachyon field which has a Born-Infeld-type action.We drive the Hamilton-Jacobi equation for the cosmological dynamics of tachyon inflation and the mode equations for the scalar and tensor ...
HU Zhijuan, YAN Aimin
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BACK REACTION OF COSMOLOGICAL PERTURBATIONS [PDF]
COSMO-99, 2000 The presence of cosmological perturbations affects the background metric and matter configuration in which the perturbations propagate. This effect, studied a long time ago for gravitational waves, also is operational for scalar gravitational fluctuations, inhomogeneities which are believed to be more important in inflationary cosmology.
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The Daily Atmospheric Ionospheric Limb Imager (DAILI) CubeSat Experiment
Journal of Geophysical Research: Space Physics, Volume 131, Issue 9, September 2026.Abstract The Daily Atmospheric Ionospheric Limb Imager (DAILI) (Daily Atmospheric and Ionospheric Limb Imager) mission utilized a 6U CubeSat, deployed at about 410 km altitude in a 51‐degree orbit, to make simultaneous daytime limb measurements in two colors; at 630 nm to measure the OI (630 nm) redline and at 765 nm to measure the O2 ${\mathrm{O}}_{2}$
James H. Hecht +15 more
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