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The current big-bang cosmological model requires re-introduction of Einstein's "regretted" old cosmological constant to fit the astronomical measurements of supernova Ia magnitude versus redshift. The physical basis of the cosmological…

Astrophysics · Physics 2007-05-23 Charles B. Leffert

Based on detailed models for the explosions, light curves and NLTE-spectra, evolutionary effects of Type Ia Supernovae (SNe Ia) with redshift have been studied to evaluate their size on cosmological time scales,how the effects can be…

Astrophysics · Physics 2007-05-23 Peter Hoeflich

This review gives an update of the cosmological use of SNe Ia and the progress made in testing their properties from the local universe to high-z. The cosmological road from high-z supernovae down to Galactic SNe Ia is followed in search of…

Astrophysics · Physics 2009-11-07 P. Ruiz-Lapuente

Due to their high luminosity at maximum and degree of homogeneity, Type Ia supernovae have been extensively used for cosmological purpouses, in particular to estimate extragalactic distances and the Hubble constant. Recently the number of…

Astrophysics · Physics 2007-05-23 Inma Dominguez , Peter Hoeflich , Oscar Straniero , Craig Wheeler

The magnitude-redshift relation is one of the tools for a direct observational approach to cosmology. The discovery of high redshift Type Ia supernovae (SNIa) and their use as ``standard candles'' has resurrected interest in this approach.…

Astrophysics · Physics 2008-11-26 Marie-Noëlle Célérier

Determination of the expansion and acceleration history of the universe is one of the fundamental goals of cosmology. Detailed measurements of these rates as a function of redshift can provide new physical insights into the nature and…

Astrophysics · Physics 2009-11-07 Ruth A. Daly , S. G. Djorgovski

The results from the Supernova Cosmology Project indicate a relation between cosmic distance and redshift that corresponds to an accelerating Universe, and, as a consequence, the presence of an energy component with negative pressure. This…

Astrophysics · Physics 2007-05-23 Daniel Enstrom , Sverker Fredriksson , Johan Hansson

The current observations are usually explained by an accelerating expansion of the present universe. However, with the present quality of the supernovae Ia data, the allowed parameter space is wide enough to accommodate the decelerating…

Astrophysics · Physics 2009-11-07 R. G. Vishwakarma

Determination of the rates at which supernovae of Type Ia (SNe Ia) occur in the early Universe can give signatures of the time spent by the binary progenitor systems to reach explosion and of the geometry of the Universe. Observations made…

Astrophysics · Physics 2009-10-30 P. Ruiz-Lapuente , R. Canal

Cosmic acceleration is investigated through a kink-like expression for the deceleration parameter (q). The new parametrization depends on the initial (q_i) and final (q_f) values of q, on the redshift of the transition from deceleration to…

Astrophysics · Physics 2009-06-23 Emille E. O. Ishida , Ribamar R. R. Reis , Alan V. Toribio , Ioav Waga

Subject of this contribution is to demonstrate that the observed faintness of the supernovae at the high redshift can be considered as a manifestation of quantum effects at cosmological scales. We show that observed redshift distribution of…

Astrophysics · Physics 2007-05-23 V. V. Kuzmichev

The large-scale dynamics of the universe is generally described in terms of the time-dependent scale factor $a(t)$. To make contact with observational data, the $a(t)$ function needs to be related to the observable $z(r)$ function, redshift…

General Physics · Physics 2025-06-17 Jan Stenflo

I review the use of Type Ia supernovae (SNe Ia) for cosmological distance determinations. Low-redshift SNe Ia (z <~ 0.1) demonstrate that the Hubble expansion is linear, that H_0 = 65 +/- 2 (statistical) km/s/Mpc, and that the properties of…

Astrophysics · Physics 2007-05-23 Alexei V. Filippenko

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…

General Relativity and Quantum Cosmology · Physics 2015-06-17 F. Shojai , A. Shojai

The first observational evidence for cosmic acceleration appeared from Type Ia supernovae (SNe Type Ia) Hubble diagram from two different groups. However, the empirical treatment of SNe Type Ia and their ability to show cosmic acceleration…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-01 Darshan Kumar , Akshay Rana , Deepak Jain , Shobhit Mahajan , Amitabha Mukherjee , R. F. L. Holanda

We investigate a class of dark energy models in which the equation of state undergoes a rapid transition and for which the Hubble SN Ia diagram is known to be poorly discriminant. Interestingly enough, we find that transitions at high…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 L. D. Ferramacho , A. Blanchard , Y. Zolnierowski , A. Riazuelo

We review the use of Type Ia supernovae for cosmological distance determinations. Low-redshift SNe Ia (z < 0.1) demonstrate that the Hubble expansion is linear, that H_0 = 65 +/- 2 (statistical) km/s/Mpc, and that the properties of dust in…

Astrophysics · Physics 2009-10-31 A. V. Filippenko , A. G. Riess

As shown by Parker and Raval, quantum field theory in curved spacetime gives a possible mechanism for explaining the observed recent acceleration of the universe. This mechanism, which differs in its dynamics from quintessence models,…

Astrophysics · Physics 2009-11-07 Leonard Parker , William Komp , Daniel A. T. Vanzella

Ongoing searches for supernovae (SNe) at cosmological distances have recently started to provide a link between SN Ia statistics and galaxy evolution. We use recent estimates of the global history of star formation to compute the…

Astrophysics · Physics 2009-10-30 P. Madau , M. Della Valle , N. Panagia

Type Ia supernovae luminosities can be corrected to render them useful as standard candles able to probe the expansion history of the universe. This technique was successful applied to discover the present acceleration of the universe. As…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-17 Xiangcun Meng , Yan Gao , Zhanwen Han