Equation 5 · Fine-Tuning Without a Tuner: Selection Effects in Physics
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This equation states an equality: the expressions on both sides have the same value under the article’s assumptions. Read the equation part by part below; each part has a contextual explanation and a link to its mathematical background.
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Symbol Omega_M
Omeg is part of the quantity the equation computes from the expression on the right.
=
The expressions on both sides represent the same quantity under the stated assumptions.
See an illustrated explanation →subscript
The lower label selects a particular version, component, or indexed member of the quantity. For example, x₀ and xₜ can be values at different positions.
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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…
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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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