Results 61 to 70 of about 6,292 (199)

H0 tension in torsion-based modified gravity

Nuclear Physics B, 2023
The rising concern in the Hubble constant tension (H0 tension) of the cosmological models motivates the scientific community to search for alternative cosmological scenarios that could resolve the H0 tension.
Sanjay Mandal, Oleksii Sokoliuk, Sai Swagat Mishra, P.K. Sahoo   +3 more
doaj   +1 more source

Geometric Characterization of LEO–GEO Inter‐Satellite Links for Bidirectional Communications

International Journal of Satellite Communications and Networking, EarlyView.
ABSTRACT Incorporating geosynchronous Earth orbit (GEO) and low Earth orbit (LEO) satellites can extend communication services far beyond the reach of terrestrial infrastructure. A key enabler of such architectures is the establishment of inter‐satellite links (ISLs) between LEOs and GEOs to support bidirectional communications.
Muhammad Furqan, Lingfeng Ye, Yanming Feng   +2 more
wiley   +1 more source

International Graduates' Stay Rate, Country‐Level Economic Differences and Social Networks: Evidence From 25 European Countries

European Journal of Education, Volume 61, Issue 3, September 2026.
ABSTRACT This paper investigates the relationship between the stay rate of international university graduates, economic characteristics of their origin and destination countries, and proxies of their social networks. It contributes to the literature by jointly testing predictions of the neoclassical and migration network theories using regression ...
Filip Němeček
wiley   +1 more source

JWST Observations Reject Unrecognized Crowding of Cepheid Photometry as an Explanation for the Hubble Tension at 8σ Confidence

The Astrophysical Journal Letters
We present high-definition observations with the James Webb Space Telescope (JWST) of >1000 Cepheids in a geometric anchor of the distance ladder, NGC 4258, and in five hosts of eight Type Ia supernovae, a far greater sample than previous studies with ...
Adam G. Riess, Gagandeep S. Anand, Wenlong Yuan, Stefano Casertano, Andrew Dolphin, Lucas M. Macri, Louise Breuval, Dan Scolnic, Marshall Perrin, Richard I. Anderson   +9 more
doaj   +1 more source

Evidence for dynamical dark energy with an evolving Hubble constant

Astronomy & Astrophysics
Context. Hubble constant tension, together with the recent indications of dynamical dark energy proposed from the Dark Energy Spectroscopic Instrument (DESI) baryon acoustic oscillation (BAO) measurements, poses significant challenges for the standard ...
Wang Yi-Ying, Li Yin-Jie, Fan Yi-Zhong
doaj   +1 more source

Existence of Solutions of Semilinear Wave Equations With Time‐Dependent Propagation Speed and Time Derivative Nonlinearity

Mathematical Methods in the Applied Sciences, Volume 49, Issue 9, Page 8681-8690, June 2026.
ABSTRACT Consider wave equations with time derivative nonlinearity and time‐dependent propagation speed which are generalized versions of the wave equations in the Friedmann–Lemaître–Robertson–Walker (FLRW) spacetime, the de Sitter spacetime and the anti‐de Sitter space time.
Kimitoshi Tsutaya, Yuta Wakasugi
wiley   +1 more source

Determining the Hubble constant using Giant extragalactic HII regions and HII galaxies [PDF]

, 2012
We report the first results of a long term program aiming to provide accurate independent estimates of the Hubble constant (H₀) using the L(Hβ) − σ distance estimator for Giant extragalactic HII regions (GEHR) and HII galaxies.
Elena Kirilovsky Terlevich, Manolis Plionis, RICARDO CHAVEZ MURILLO, ROBERTO GIOVANNI TERLEVICH AFONSO   +3 more
core  

Clarifying the Hubble Constant Tension

, 2019
Our best estimate of the Universe's current expansion rate (the Hubble constant) from the local Universe (via the Cepheid distance ladder) is in four-sigma tension with the value extrapolated from cosmic microwave background data assuming the standard ...
Stephen Feeney (8173554), Stephen Feeney
core   +1 more source

Background Instability of Quintessence Model in Light of Entropy and Distance Conjecture

Fortschritte der Physik, Volume 74, Issue 6, June 2026.
ABSTRACT We apply the covariant entropy bound argument supporting the de Sitter swampland conjecture to the quintessence model, to find out the condition for the background to be unstable. More concretely, the background is unstable when the matter entropy given by the species number of the effective field theory increases more rapidly than the ...
Min‐Seok Seo
wiley   +1 more source

The Hubble Constant from Blue Type Ia Supernovae

The Astrophysical Journal
There is a persistent tension of about 5 σ –6 σ between the value of the Hubble constant, as derived from the local distance ladder versus the cosmic microwave background, signaling either unaccounted for systematics in the measurements or “new physics,”
Christa Gall, Luca Izzo, Radosław Wojtak, Jens Hjorth   +3 more
doaj   +1 more source