Equation 14 · Part 1 · Radioactive Clocks: How Nuclear Physics Gave Evolution Its Time
Symbol N_87
What this part means
7 is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Its job in the formula
7 is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Full expression→Symbol N_87→Article meaning
The passage around this formula
where is each mineral’s measured present-day strontium-87 to strontium-86 ratio, is the shared initial ratio recovered as the line’s intercept, and / is each mineral’s measured rubidium-87 to strontium-86 ratio [ 18 ] . The initial composition is no longer an assumption fed into the calculation; it is an output the data themselves supply, and a poor fit to a straight line is itself a warning that the minerals did not, in fact, share a common origin or have remained closed systems since.
Learn the underlying idea
A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.
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Sources cited in the surrounding passage
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