The First Acoustics Peak in CMBR and Cosmic Total Density
نویسنده
چکیده
Boomerang measured the first peak in CMBR to be at location of lD = 196±6, which excites our strong interesting in it. A widely cited formula is lD ≃ 200Ω T to estimate the cosmic total density. Weinberg shows it is not correct and should be lD ∝ Ω T near the interest point (Ωm,ΩΛ) = (0.3, 0.7). We show further that it should be lD ∝ Ω T Ω m or Ω T Ω Λ near the same point in the more veracious sense if we consider the effect from the sound horizon. We draw a contour graph for the peak location, show that the recent data favor to a closed universe with about ΩT ≃ 1.03. If we insist on obtaining a flat universe, a point (0.36, 0.64), i.e., more matter and less vacuum energy, is still possible, which has a more right-side first peak lD = 208 in CMBR and a smaller acceleration parameter −q0 = 0.10 for the z = 0.4 redshift SNIa.
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