Does the Fine‐Structure Constant Vary with Cosmological Epoch?
نویسندگان
چکیده
منابع مشابه
Does the fine-structure constant vary with cosmological epoch?
We use the strong nebular emission lines of O iii, 5007 Å and 4959 Å, to set a robust upper limit on the time dependence of the fine structure constant. We find |α−1dα(t)/dt| < 2 × 10−13 yr−1, corresponding to ∆α/α(0) = (0.7± 1.4) × 10−4 for quasars with 0.16 < z < 0.80 obtained from the SDSS Early Data Release. Using a blind analysis, we show that the upper limit given here is invariant with r...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2004
ISSN: 0004-637X,1538-4357
DOI: 10.1086/379971