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Equation 1 · Part 2 · How Stochastic Thermodynamics and Complex Systems Actually Work

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ΔF\Delta F
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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.

The passage around this formula

Pull a molecule apart with an optical trap or an atomic force microscope and record the work done. Repeat the pull hundreds of times under identical conditions and the recorded work values scatter — sometimes wildly — because thermal noise contributes to every individual trajectory. That scatter looks like it should make the equilibrium free-energy difference Δ\Delta F unrecoverable from irreversible, far-from-equilibrium pulls.

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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.

Open the illustrated addition and subtraction in an equation guide →

Sources cited in the article section

These citations provide research context; check each source for the exact claim it supports.