English
Related papers

Related papers: Supernova Magnitude Evolution and PAge Approximati…

200 papers

Modified $f(R)$ gravity in the Palatini approach has been presently applied to Cosmology as a realistic alternative to dark energy. In this concern, a number of authors have searched for observational constraints on several $f(R)$ gravity…

Astrophysics · Physics 2009-06-23 F. C. Carvalho , E. M. Santos , J. S. Alcaniz , J. Santos

Type Ia supernovae (SNe Ia) serve as the most crucial standardizable candles in cosmology, providing direct measurements of the universe's expansion history. However, it is well-known that the post-standardization brightness of SNe Ia is…

Astrophysics of Galaxies · Physics 2025-03-27 Chul Chung , Seunghyun Park , Junhyuk Son , Hyejeon Cho , Young-Wook Lee

The lower limit on the age of the universe derived from globular cluster dating techniques, which previously strongly motivated a non-zero cosmological constant, has now been dramatically reduced, allowing consistency for a flat matter…

Astrophysics · Physics 2011-02-11 Lawrence M. Krauss

Rapid progress has been made recently toward the measurement of cosmological parameters. Still, there are areas remaining where future progress will be relatively slow and difficult, and where further attention is needed. In this review,…

Astrophysics · Physics 2009-10-31 Wendy L. Freedman

This manuscript revisits the phenomenological emergent dark energy model (PEDE) by confronting it with recent cosmological data from early and late times. In particular we analyze PEDE model by using the baryon acoustic oscillation (BAO)…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-11 A. Hernández-Almada , M. L. Mendoza-Martínez , Miguel A. García-Aspeitia , V. Motta

We define the cosmological parameters $H_{c,0}$, $\Omega_{m,c}$ and $\Omega_{\Lambda, c}$ within the Conformal Cosmology as obtained by the homogeneous approximation to the conformal-invariant generalization of Einstein's General Relativity…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Danilo Behnke , David Blaschke , Victor Pervushin , Denis Proskurin

We have previously shown that the type Ia supernovae data by Riess et al. match the prediction of the magnitude-redshift relation in the plasma-redshift cosmology. In this article, we also show that the recent SNLS data, which have a…

Astrophysics · Physics 2007-05-23 Ari Brynjolfsson

Over the last 20 years, supernovae have become a key tool to constrain the expansion history of the Universe through the construction of Hubble diagrams, using luminosity distances to supernovae belonging to the "Ia" subtype. This technique…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-13 Pierre Astier

In this work, we consider the cosmological constraints on the new agegraphic dark energy (NADE) proposed in arXiv:0708.0884, by using the observational data of type Ia supernovae (SNIa), the shift parameter from cosmic microwave background…

Astrophysics · Physics 2008-11-26 Hao Wei , Rong-Gen Cai

An interesting way to calibrate the absolute magnitudes of remote Type Ia supernovae (SNe Ia) that are well out in the Hubble flow, and thus determine the value of the Hubble constant, H_0, has been introduced by van den Bergh. His approach…

Astrophysics · Physics 2007-05-23 David Branch , Adam Fisher , E. Baron , Peter Nugent

We revisit cosmological neutrino mass bounds when a fraction of dark matter is allowed to decay to massless dark radiation. By compensating the late-time increase in the matter density induced by neutrinos becoming non-relativistic,…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-04 Thomas Montandon , Vivian Poulin , Thomas Rink , Thomas Schwetz

Nowadays, efforts are being devoted to the study of alternative cosmological scenarios in which modifications of General Relativity have been proposed to explain the late cosmic acceleration without assuming the existence of dark energy. In…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-17 Bruno Ribeiro , Armando Bernui , Marcela Campista

Understanding the evolution of dark energy poses a significant challenge in modern cosmology, as it is responsible for the universe's accelerated expansion. In this study, we focus on a specific $f(T)$ cosmological model and analyze its…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-14 A. Zhadyranova , M. Koussour , S. Bekkhozhayev , V. Zhumabekova , J. Rayimbaev

Particle acceleration in the dynamically evolving environment of Supernova Remnants is discussed in the framework of a genuinely time-dependent nonlinear theory, assuming spherical symmetry. As a consequence the dependence of injection on…

Astrophysics · Physics 2007-05-23 H. J. Voelk

In this paper we discuss a cosmological model for a universe with self-regulating features. We set up the theoretical framework for the model and determine the time evolution of the scale-factor $a(t)$. It is shown that such a universe…

General Relativity and Quantum Cosmology · Physics 2024-01-15 Manasse R. Mbonye

We have shown that the varying physical constant model is consistent with the recently published variational approach wherein Einstein equations are modified to include the variation of the speed of light c, gravitational constant G and…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-21 Rajendra P. Gupta

Keeping in mind the current picture of an accelerating and flat Universe, some specific dynamical models of the cosmological term $\Lambda$ have been selected for investigating the nature of dark energy. Connecting the free parameters of…

Astrophysics · Physics 2008-11-26 Saibal Ray , Utpal Mukhopadhyay , Xin-He Meng

The \HOmega\ diagram is resurrected to dramatically illustrate the nature of the key problems in physical cosmology today and the role that nuclear physics plays in many of them. In particular it is noted that the constraints on \OmegaB\…

Astrophysics · Physics 2014-10-13 Craig J. Copi , David N. Schramm

Because Type Ia supernovae (SNe Ia) are not perfect standard candles, it is important to be able to use distance-independent observables (DIOs) to define subsets of SNe Ia that are ``nearly standard candles'' or to correct SN Ia absolute…

Astrophysics · Physics 2007-05-23 David Branch , Peter Nugent , Adam Fisher
‹ Prev 1 8 9 10 Next ›