Equation 6 · Fine-Tuning Without a Tuner: Selection Effects in Physics
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Symbol Omega_Lambda
Omegambda is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
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Its accuracy depends on the assumptions and range of use described in the article.
What the article says around this equation
What actually happened next is the part worth stating precisely. In 1998, two independent supernova teams measuring the expansion history of the universe with distant Type Ia supernovae found that the expansion is accelerating, and the Supernova Cosmology Project’s analysis of forty-two high-redshift supernovae reported, for a flat universe, a matter density of = 0.28 with combined statistical and systematic uncertainties of a few hundredths, and stated that the data indicated a nonzero, positive cosmological constant at 99 percent confidence [ 3 ] . That result places the implied vacuum energy density at roughly 0.7 — a value sitting comfortably inside the…
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What actually happened next is the part worth stating precisely. In 1998, two independent supernova teams measuring the expansion history of the universe with distant Type Ia supernovae found that the expansion is accelerating, and the Supernova Cosmology Project’s analysis of forty-two high-redshift supernovae reported, for a flat universe, a matter density of = 0.28 with combined statistical and systematic uncertainties of a few hundredths, and stated that the data indicated a nonzero, positive cosmological constant at 99 percent confidence [ 3 ] . That result places the implied vacuum energy density at roughly 0.7 — a value sitting comfortably inside the “quite large” anthropic window Weinberg had described eleven years earlier, and specifically within the one-to-two-order-of-magnitude band he had flagged as anthropically interesting.
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