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Equation 4 · Part 1 · Einstein's Random Walk and the Mathematics of Genetic Drift

Symbol D

DD
DD

What this part means

D 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

D is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

The passage around this formula

with the diffusion constant D fixed by measurable quantities. Einstein derived it explicitly, from the balance between the drag on a sphere of radius P in a fluid of viscosity k and the osmotic pressure driving diffusion, as

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Learn the underlying idea

A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.

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