相关论文: Marginal evidence for cosmic acceleration from Typ…

The cosmological standard model at present is widely accepted as containing mainly things we do not understand. In particular the appearance of a Cosmological Constant, or dark energy, is puzzling. This was first inferred from the Hubble…

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…

Under the assumption that they are standard(isable) candles, the lightcurves of Type Ia supernovae have been analyzed in the framework of the standard Friedmann-Lema\^itre-Robertson-Walker cosmology to conclude that the expansion rate of…

The accelerating expansion of the universe is one of the most profound discoveries in modern cosmology, pointing to a universe in which 70% of the mass-energy density has an unknown form spread uniformly across the universe. This result has…

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…

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…

The discovery of cosmic acceleration is one of the most important developments in modern cosmology. The observation, thirteen years ago, that type Ia supernovae appear dimmer that they would have been in a decelerating universe followed by…

We test the present expansion of the universe using supernova type Ia data without making any assumptions about the matter and energy content of the universe or about the parameterization of the deceleration parameter. We assume the…

In the late 1990's, observations of 93 Type Ia supernovae were analysed in the framework of the FLRW cosmology assuming these to be `standard(isable) candles'. It was thus inferred that the Hubble expansion rate is accelerating as if driven…

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…

It is generally argued that the present cosmological observations support the accelerating models of the universe, as driven by the cosmological constant or `dark energy'. We argue here that an alternative model of the universe is possible…

Over the past decade, supernovae have emerged as some of the most powerful tools for measuring extragalactic distances. A well developed physical understanding of type II supernovae allow them to be used to measure distances independent of…

While low-z Type Ia supernovae are used to measure the present rate of expansion of the Universe, high-z Type Ia measure its variation due to the cosmic matter-energy content. Results from those determinations imply a low matter density…

Observational astronomy has shown significant growth over the last decade and has made important contributions to cosmology. A major paradigm shift in cosmology was brought about by observations of Type Ia supernovae. The notion that the…

The observation that Type Ia supernovae are fainter than expected given their red shifts has led to the conclusion that the expansion of the universe is accelerating. The widely accepted hypothesis is that this acceleration is caused by a…

Observational data for type Ia supernovae, shows that the expansion of the universe is accelerated. This accelerated expansion can be described by a cosmological constant or by dark energy models like quintessence. An interesting question…

We present a short (and necessarily incomplete) review of the evidence for the accelerated expansion of the Universe. The most direct probe of acceleration relies on the detailed study of supernovae (SN) of type Ia. Assuming that these are…

Cosmology is undergoing an explosive period of activity, fueled both by new, accurate astrophysical data and by innovative theoretical developments. Cosmological parameters such as the total density of the Universe and the rate of…

Context: The cosmological concordance model ($\Lambda$CDM) matches the cosmological observations exceedingly well. This model has become the standard cosmological model with the evidence for an accelerated expansion provided by the type Ia…

Type Ia supernovae (SNe Ia) provided the first strong evidence that the expansion of the universe is accelerating. With SN samples now more than ten times larger than those used for the original discovery and joined by other cosmological…