Symbol rho_Lambda^naive QFT estimate
rhambdaive QFT estimate occurs above the fraction bar. The numerator is divided by the entire denominator below it.
Read this term in its guide →Published equation contexts
Why this formula appears here
Quantum field theory predicts that empty space should carry a vacuum energy density set by the ultraviolet scales in the theory — naively, something near the Planck scale. Steven Weinberg’s 1989 review laid out the problem in its modern form: astronomical observations constrain the cosmological constant to be many orders of magnitude smaller than any of the contributions particle theory predicts for it, and the review catalogues five distinct classes of proposed solution, from supersymmetry to anthropic reasoning, none of which he judged fully satisfactory at the time [ 2 ] . The often-quoted headline is that the naive theoretical estimate and the observed value differ by around 120 orders…
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Symbol rho_Lambda^observed
rhambdbserved occurs below the fraction bar. The quantity above the bar is divided by this expression; zero is excluded as a denominator.
Read this term in its guide →How to interpret it
With a fixed numerator, increasing a nonzero denominator reduces the fraction.
Research cited beside this formula
Published contexts (1)
A symbol can carry a different meaning in another article. Each occurrence keeps its own guide and term definitions.
Equation 1 · Evolutionary Physics
Fine-Tuning Without a Tuner: Selection Effects in Physics
This mathematical expression combines the displayed quantities; its precise role follows from the surrounding article text.
Quantum field theory predicts that empty space should carry a vacuum energy density set by the ultraviolet scales in the theory — naively, something near the Planck scale. Steven Weinberg’s 1989 review laid out the problem in its modern form: astronomical observations constrain the cosmological constant to be many orders of magnitude smaller than any of the contributions particle theory predicts for it, and the review catalogues five distinct classes of proposed solution, from supersymmetry to anthropic reasoning, none of which he judged fully satisfactory at the time [ 2 ] . The often-quoted headline is that the naive theoretical estimate and the observed value differ by around 120 orders…
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