Equation 16 · Part 2 · The Arrow of Time and the Engine of Evolution
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What this part means
Capital delta attached to a quantity marks a difference between two values of that quantity; the article’s sign convention determines the order.
Its job in the formula
Capital delta attached to a quantity marks a difference between two values of that quantity; the article’s sign convention determines the order.
Full expression→change→Article meaning
The passage around this formula
[ 6 ] . Where W exactly equals F , the ratio is one and the forward distribution crosses the reflected reverse distribution; away from that point, the ratio grows exponentially in how far W departs from F , which is the precise, quantitative sense in which a trajectory doing much more work than the equilibrium minimum is exponentially more typical of the forward process than of its reverse. This is the arrow of time rendered as an odds ratio rather than an inequality: not “entropy increases,” but “this particular trajectory is times more likely to have been produced running forward than running backward.”
Learn the underlying idea
Addition combines quantities; subtraction measures the signed difference between them. Parentheses show what is combined before the rest of the expression is evaluated.
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Sources cited in the surrounding passage
These citations provide research context; check each source for the exact claim it supports.