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Related papers: On the accelerated expansion of the cosmos

200 papers

We employ the Union compilation of Type Ia supernovae with a maximum likelihood analysis to search for a dark energy dipole. To approach this problem, we present a simple, computationally efficient, and largely model independent method. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 R. Cooke , D. Lynden-Bell

We revisit a model-independent estimator for cosmic acceleration based on type Ia supernovae distance measurements. This approach does not rely on any specific theory for gravity, energy content or parameterization for the scale factor or…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-02 Hermano Velten , Syrios Gomes , Vinicius C. Busti

The Supernova / Acceleration Probe (SNAP) is a proposed space-based experiment designed to study the dark energy and alternative explanations of the acceleration of the Universe's expansion by performing a series of complementary…

We discuss the testable predictions of a phenomenological model in which the accelerated expansion of the universe is the result of the action of a non-gravitational force field, rather than the effect of a negative-pressure dark-energy…

Astrophysics · Physics 2009-11-13 A. Buzzi , C. Marinoni , S. Colafrancesco

We quantify the evidence for cosmic acceleration using simulations of $H(z)$ measurements from SKA- and Euclid-like surveys. We perform a non-parametric reconstruction of the Hubble parameters and its derivative to obtain the deceleration…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-06 Carlos A. P. Bengaly

The SuperNova / Acceleration Probe (SNAP) is a space-based experiment to measure the expansion history of the Universe and study both its dark energy and the dark matter. The experiment is motivated by the startling discovery that the…

Astrophysics · Physics 2015-06-24 G. Aldering , SNAP collaboration

We present observations of 10 type Ia supernovae (SNe Ia) between 0.16 < z < 0.62. With previous data from our High-Z Supernova Search Team, this expanded set of 16 high-redshift supernovae and 34 nearby supernovae are used to place…

We discuss recent evidence for an accelerating Universe from measurements of type Ia supernovae at high redshift, and describe tests of various systematic effects such as extinction and evolution that could be biasing the cosmological…

Astrophysics · Physics 2007-05-23 Saurabh Jha , the High-Z Supernova Search Team

Parameters that quantify the acceleration of cosmic expansion are conventionally determined within the standard Friedmann-Lemaitre-Robertson-Walker (FLRW) model, which fixes spatial curvature to be homogeneous. Generic averages of…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-15 Lawrence H. Dam , Asta Heinesen , David L. Wiltshire

The accelerating expansion of the Universe is one of the most surprising and potentially profound discoveries of modern cosmology. Measuring the acceleration well enough to meaningfully constrain interesting physical models requires…

Astrophysics · Physics 2009-11-13 G. Aldering

Observations of SN 1997ff at z ~ 1.7 favor the accelerating Universe interpretation of the high-redshift type Ia supernova data over simple models of intergalactic dust or SN luminosity evolution. Taken at face-value, they provide direct…

Astrophysics · Physics 2009-12-30 Michael S. Turner , Adam Riess

Recent experimental results find strong indications that the universe is flat, while other experimental results from supernovae Ia observations have been interpreted to show that, not only that there is an accelerating expansion of the…

Astrophysics · Physics 2012-08-27 George A. Baker,

A recent analysis of the Supernova Ia data claims a 'marginal' ($\sim3\sigma$) evidence for a cosmic acceleration. This result has been complemented with a non-accelerating $R_{h}=ct$ cosmology, which was presented as a valid alternative to…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 Balakrishna S. Haridasu , Vladimir V. Luković , Rocco D'Agostino , Nicola Vittorio

We have shown (Colin et al., 2019) that the acceleration of the Hubble expansion rate inferred from Type Ia supernovae (SNe Ia) is, at $3.9\sigma$ significance, a dipole approximately aligned with the CMB dipole, while its monopole…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-24 Jacques Colin , Roya Mohayaee , Mohamed Rameez , Subir Sarkar

We employ Maximum Likelihood Estimators to examine the Pantheon+ catalogue of Type Ia supernovae for large scale anisotropies in the expansion rate of the Universe. The analyses are carried out in the heliocentric frame, the CMB frame, as…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-02 Animesh Sah , Mohamed Rameez , Subir Sarkar , Christos Tsagas

Observations of distant supernovae indicate that the Universe is now in a phase of accelerated expansion the physical cause of which is a mystery. Formally, this requires the inclusion of a term acting as a negative pressure in the…

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

Type Ia supernovae are a powerful cosmological probe, that gave the first strong evidence that the expansion of the universe is accelerating. Here we provide an overview of how supernovae can go further to reveal information about what is…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-05 Tamara M. Davis , David Parkinson

We give an overview of the current understanding of Type Ia supernovae relevant for their use as cosmological distance indicators. We present the physical basis to understand their homogeneity of the observed light curves and spectra and…

Astrophysics · Physics 2015-06-24 P. Hoeflich , C. Gerardy , E. Linder , H. Marion

A possible slowing down of the cosmic expansion is investigated through a cosmographic approach. By expanding the luminosity distance to fourth order and fitting the SN Ia data from the most recent compilations (Union, Constitution and…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Antonio C. C. Guimarães , José Ademir S. Lima