Kronecker delta

In mathematics, the Kronecker delta or Kronecker's delta, named after Leopold Kronecker (1823-1891), is a function of two variables, usually integers, which is 1 if they are equal, and 0 otherwise. So, for example, delta_{12} = 0, but delta_{33} = 1. It is written as the symbol δij, and treated as a notational shorthand rather than as a function.

Related Topics:
Mathematics - Leopold Kronecker - 1823 - 1891 - Integer

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:delta_{ij} = left{egin{matrix}

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1 & mbox{if } i=j \

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0 & mbox{if } i e j end{matrix} ight.

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or, using the Iverson bracket:

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: delta_{ij} = ,

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