Kronecker delta
- noun
- /ˈkroʊnɛkər ˈdɛltə/
- Specialized
:
delta de Kronecker
- The Kronecker delta equals 1 when both variables are the same and 0 otherwise.
Examples
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When i and j are not equal, the Kronecker delta yields zero.
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The Kronecker delta is frequently used to simplify expressions in linear algebra.
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In tensor notation, the Kronecker delta acts as the identity matrix.
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The function Kronecker delta is essential in linear algebra.
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In physics, the Kronecker delta simplifies many equations.
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Mathematicians often use the Kronecker delta to express conditions in proofs.
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In many equations, the Kronecker delta helps eliminate terms that do not contribute.
Surface Forms
Morphology
Kronecker + delta
Kronecker is a proper name (a mathematician) and 'delta' is usually understood as a Greek letter or a sign of change; their combination is a conventional, technical label for a specific binary function in mathematics whose meaning (1 if indices equal, 0 otherwise) is not derivable from the parts. As a named mathematical term this is language- and discipline-specific, so a B1 learner who only knows the constituents would not be able to infer the MWE's meaning.
Etymology
The term Kronecker delta is named after the mathematician Leopold Kronecker and works like a simple on/off rule. It gives 1 when two numbers are the same and 0 when they are different, so it acts like a tiny switch that says 'yes' for equal items and 'no' for unequal ones.
