相关论文: Marginal evidence for cosmic acceleration from Typ…
The deceleration parameter q as the diagnostic of the cosmological accelerating expansion is investigated. By expanding the luminosity distance to the fourth order of redshift and the so-called y-redshift in two redshift bins and fitting…
The discovery that the cosmic expansion is accelerating has been followed by an intense theoretical and experimental response in physics and astronomy. The discovery implies that our most basic notions about how gravity work are violated on…
The cosmological model best capable of fitting current observational data features two separate epochs during which the Universe is accelerating. During the earliest stages of the Universe, such acceleration is known as cosmological…
The free parameters of a flat accelerating model without dark energy are constrained by using Supernovae type Ia and observational H(z) data. Instead of the vacuum dominance, the present accelerating stage in this modified Einstein-de…
The observed luminosity deficit of Type Ia supernovae (SNe Ia) at high redshift z can be explained by partial conversion to weak vector bosons of photons crossing large-scale electroweak domain boundaries, making Hubble acceleration only…
The good match of the type Ia supernova (SNIa) Hubble Diagram to the prediction of a not-unreasonable cosmological world model shows that measurements of standard stars and their comparison with point sources down to m=25 mag is good to…
Type Ia supernovae (SNe\,Ia) serve as crucial cosmological distance indicators because of their empirical consistency in peak luminosity and characteristic light curve decline rates. These properties facilitate them to be standardized…
Cosmology is very exciting for three reasons. There is a very successful standard model - the hot big bang - which describes the evolution of the Universe from 10^{-2} sec onward. There are bold ideas, foremost among them are inflation and…
In this paper we propose that the accelerating expansion of the present matter-dominated universe, as suggested by the recent distance measurements of type Ia supernovae, is generated along with the evolution of space in extra dimensions.…
A higher value of Hubble constant has been obtained from measurements with nearby Type Ia supernovae, than that obtained at much higher redshift. With the peculiar motions of their hosts, we find that the matter content at such low redshift…
We show that detailed exploration of the $1<z<2$ redshift region can provide for definitive testing not only of the standard inflationary cosmological paradigm with its fine-tuned cosmological constant and its mysteriously late ($z<1$)…
It is pointed out that very recent results based on supernovae observations that the universe will accelerate and expand for ever with ever decreasing density have been predicted in a recent cosmological model which also deduces hitherto…
A strictly linear evolution of the cosmological scale factor is surprisingly an excellent fit to a host of cosmological observations. Any model that can support such a coasting presents itself as a falsifiable model as far as classical…
A fundamental presupposition of modern cosmology is the Copernican Principle; that we are not in a central, or otherwise special region of the Universe. Studies of Type Ia supernovae, together with the Copernican Principle, have led to the…
The cosmological constant, i.e., the energy density stored in the true vacuum state of all existing fields in the Universe, is the simplest and the most natural possibility to describe the current cosmic acceleration. However, despite its…
Review article on the cosmological implications of Type Ia Supernovae for Europhysics News.
In this essay, I present an alternative explanation for the cosmic acceleration which appears as a consequence of recent high redshift Supernova data. In the usual interpretation, this cosmic acceleration is explained by the presence of a…
The principles of General Relativity allow for a non-vanishing cosmological constant, which can possibly be interpreted at least partially in terms of quantum-fluctuations of matter fields. Depending on sign and magnitude it can cause…
The extreme luminosity and their fairly unique temporal behaviour have made supernovae a superb tool to measure distances in the universe. As complex astrophysical events they provide interesting insights into explosion physics, explosive…
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…