In cosmological models

In the original work of Hoyle and Fowler, P(A(M)) represents estimation uncertainty, from measurement precision and model diversity, of a single character selected for its sensitivity and relevance to a specific experimental problem. In cosmological models of either type. P(A(AZ)) can also represent a distribution over alternative characters regarded as substitutes for identifying the posterior distribution we wish to specify. 

In cosmological models A is routinely ignored because of its vanishingly small value, but in particle physics it has a non-zero value, arising from the presence of infinitely many virtual particles that constantly fluctuate in and out of the vacuum. Experimental estimates of spatial curvature predict... 

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