کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
10723049 | 1033827 | 2010 | 6 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Observational constraints on f(T) theory
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
فیزیک و نجوم
فیزیک هسته ای و انرژی بالا
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
The f(T) theory, which is an extension of teleparallel, or torsion scalar T, gravity, is recently proposed to explain the present cosmic accelerating expansion with no need of dark energy. In this Letter, we first perform the statefinder analysis and Om(z) diagnostic to two concrete f(T) models, i.e., f(T)=α(âT)n and f(T)=âαT(1âepT0/T), and find that a crossing of phantom divide line is impossible for both models. This is contrary to an existing result where a crossing is claimed for the second model. We, then, study the constraints on them from the latest Union 2 Type Ia Supernova (Sne Ia) set, the baryonic acoustic oscillation (BAO), and the cosmic microwave background (CMB) radiation. Our results show that at the 95% confidence level Ωm0=0.272â0.032+0.036, n=0.04â0.33+0.22 for Model 1 and Ωm0=0.272â0.034+0.036, p=â0.02â0.20+0.31 for Model 2. A comparison of these two models with the ÎCDM by the ÏMin2/dof (dof: degree of freedom) criterion indicates that ÎCDM is still favored by observations. We also study the evolution of the equation of state for the effective dark energy in the theory and find that Sne Ia favors a phantom-like dark energy, while Sne Ia + BAO + CMB prefers a quintessence-like one.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Physics Letters B - Volume 693, Issue 4, 11 October 2010, Pages 415-420
Journal: Physics Letters B - Volume 693, Issue 4, 11 October 2010, Pages 415-420
نویسندگان
Puxun Wu, Hongwei Yu,