Equation 12 · Part 1 · Radioactive Clocks: How Nuclear Physics Gave Evolution Its Time
Symbol R_t
What this part means
each mineral’s measured present-day strontium-87 to strontium-86 ratio.
Its job in the formula
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 R_t→Article meaning
Where the article explains it
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 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.
Open the illustrated subscripts: which member of a family? guide →
See this notation across published equations →
Sources cited in the surrounding passage
These citations provide research context; check each source for the exact claim it supports.