The nature of dark energy

Amendola, Luca; Quercellini, Claudia; Tocchini-Valentini, Domenico; Pasqui, Alessandro

doi:10.1590/s0103-97332002000500002

Cited by 4 publications

(6 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This requires however the knowledge of the behavior of the perturbation throughout the post-decoupling era, not only during the final accelerated stage. In detailed models such as the string-inspired one discussed in Amendola et al (2002) it can be shown that it is indeed possible to match the observed level of fluctuations.…”

Section: Growth Of Perturbationsmentioning

confidence: 92%

“…As an aside, let us comments on the consequences of the above results on an application of the anthropic principle. According to Vilenkin (2002), that generalized previous analyses by Weinberg (1987), the amount of dark energy cannot exceed too much the observed value because otherwise the perturbation growth stops before galaxies can form, thereby preventing life. In particular, the anthropic principle "predicts" that Ω φ has to be significanty smaller than unity, i.e.…”

Section: Growth Of Perturbationsmentioning

confidence: 95%

“…and where the dimensionless field φ = κφ/2 has been introduced to match the definition of Damour & Esposito-Farese (1992), Hagiwara et al (2002) and Will (2002).…”

Section: When Did the Acceleration Start?mentioning

confidence: 99%

See 2 more Smart Citations

Acceleration at z > 1?

Amendola

2003

Monthly Notices of the Royal Astronomical Society

142

View full text Add to dashboard Cite

Most models of dark energy predict the beginning of the accelerated epoch at z 1. However, there is no observational or theoretical evidence in favour of such a recent start of the cosmic acceleration. In fact, a model of dark energy coupled to dark matter is explicitly constructed which (a) is accelerated even at high z, (b) allows structure formation during acceleration, and (c) is consistent with the Type Ia supernovae Hubble diagram, including the farthest known supernova SN1997ff at z ≈ 1.7. It is shown that the accelerated epoch in this model could have started as early as z ≈ 5.

show abstract

Section: Growth Of Perturbationsmentioning

confidence: 92%

Section: Growth Of Perturbationsmentioning

confidence: 95%

See 1 more Smart Citation

Acceleration at z > 1?

Amendola

2003

Monthly Notices of the Royal Astronomical Society

142

View full text Add to dashboard Cite

show abstract

“… See Avelino, Martins, & Pinto (2002) for a recent application of theGott et al (2001) median statistics technique.4 Of course, comparing the predictions of dark energy dominated models to observational measurements is another way to check for the presence of dark energy. In the near future neoclassical cosmological tests that hold significant promise include those based on CMB anisotropy (see, e.g.,Brax, Martin, & Riazuelo 2000;Amendola et al 2002), gravitational lensing (see, e.g.,Ratra & Quillen 1992;Waga & Frieman 2000;Chae et al 2002), Type Ia supernova redshift-apparent magnitude (see, e.g.,Podariu & Ratra 2000;Waga & Frieman 2000;Leibundgut 2001), redshiftcounts (see, e.g.,Huterer & Turner 2001;Levine, Schulz, & White 2002), and redshift-angular…”

mentioning

confidence: 99%

Median Statistics and the Mass Density of the Universe

Chen¹,

Ratra²

2003

PUBL ASTRON SOC PAC

View full text Add to dashboard Cite

We use weighted mean and median statistics techniques to combine individual estimates of Omega_m0, the present mean mass density in non-relativistic matter, and determine the observed values and ranges of Omega_m0 from different combinations of data. The derived weighted mean Omega_m0 values are not good representatives of the individual measurements, under the assumptions of Gaussianity and negligible correlation between the individual measurements. This could mean that some observational error bars are under-estimated. Discarding the most discrepant about 5% of the measurements generally alleviates but does not completely resolve this problem. While the results derived from the different combinations of data are not identical, they are mostly consistent, and a reasonable summary of the median statistics analyses is 0.2 <= Omega_m0 <= 0.35 at two standard deviations.Comment: 17 pages, submitted to Ap

show abstract

“…He pointed out how recent supernovae Ia observations [9,10] call for an acceleration expansion of the universe, which together with recent cosmic microwave, large-scale structure and lensing data give a rather strong indication that the matter (energy) content of the universe is basically composed of dark matter (∼ 30%), dark energy (∼ 70%), baryonic matter (very few percent). For more details and references see his review paper in this issue [11].…”

Section: Plenary and Parallel Talksmentioning

confidence: 99%

Summary talk on Cosmology and Gravitation XXII Brazilian National Meeting on Particles and fields

Rebouças¹

2002

Braz. J. Phys.

View full text Add to dashboard Cite

The nature of dark energy

Cited by 4 publications

References 14 publications

Acceleration at z > 1?

Acceleration at z > 1?

Median Statistics and the Mass Density of the Universe

Summary talk on Cosmology and Gravitation XXII Brazilian National Meeting on Particles and fields

Contact Info

Product

Resources

About