Equation 7 · Part 1 · Structure from Sequence: What Protein Folding Prediction Did and Did Not Settle
Symbol L
What this part means
L 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
L 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 L→Article meaning
The passage around this formula
Two things about this argument are routinely misreported. First, the specific numbers are illustrative and depend entirely on the assumed and sampling rate — they are a scaling argument dressed as a calculation. What survives any choice of parameters is that the configuration count grows exponentially in L while folding times do not. Second, Levinthal was not proposing that folding is a random search and then expressing surprise. The arithmetic was constructed precisely to rule that mechanism out. The paradox is a paradox only for someone who assumed search in the first place.
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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Sources cited in the article section
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