کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
8191407 | 1528865 | 2011 | 7 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Detecting the cosmic acceleration with current data
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موضوعات مرتبط
مهندسی و علوم پایه
فیزیک و نجوم
فیزیک هسته ای و انرژی بالا
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
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 SNIa data (Union2), the marginalized likelihood distribution of the current deceleration parameter shows that the cosmic acceleration is still increasing, but there might be a tendency that the cosmic acceleration will slow down in the near future. We also fit the Hubble evolution data together with SNIa data by expanding the Hubble parameter to the third order, showing that the present decelerating expansion is excluded within 2Ï error. Further exploration on this problem is also approached in a non-parametrization method by directly reconstructing the deceleration parameter from the distance modulus of SNIa, which depends neither on the validity of general relativity nor on the content of the universe or any assumption regarding cosmological parameters. More accurate observation datasets and more effective methods are still in need to make a clear answer on whether the cosmic acceleration will keep increasing or not.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Physics Letters B - Volume 706, Issues 2â3, 6 December 2011, Pages 116-122
Journal: Physics Letters B - Volume 706, Issues 2â3, 6 December 2011, Pages 116-122
نویسندگان
Rong-Gen Cai, Zhong-Liang Tuo,