Equation 14 · Error Correction Is the Whole Problem in Quantum Computing
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Read the formula alongside the article passage below. Each part has a deeper page with its role in the equation, the supporting passage and nearby citations.
This equation states an equality: the expressions on both sides have the same value under the article’s assumptions. Read the equation part by part below; each part has a contextual explanation and a link to its mathematical background.
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=
The expressions on both sides represent the same quantity under the stated assumptions.
See an illustrated explanation →subtraction
Subtract the following term or group from the preceding one. A leading minus marks a negative quantity.
subscript
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superscript
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What the article says around this equation
Distance d is the weight of the smallest undetectable logical error. A distance- d code corrects up to (d-1)/2 errors. For the planar surface code in its standard rotated layout, the physical cost of one logical qubit is . counting data and measure qubits together. A distance-7 patch therefore occupies ninety-seven physical qubits, and that is a memory holding one logical qubit, doing nothing else. It performs no gate, produces no non-Clifford operation, and reserves no routing space.
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