Are Products of Dirac Delta Functions Well-Defined?

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SUMMARY

The discussion centers on the mathematical properties of Dirac delta functions, specifically the products of distributions. It concludes that expressions such as δ(z*-z0*)δ(z+z0) and δ(z*+z0*)δ(z-z0) are not well-defined due to the nature of distributions. The Dirac delta function is classified as a distribution rather than a conventional function, and while it can be multiplied by smooth functions, multiplying two distributions does not yield a clear meaning.

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Muthumanimaran
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Homework Statement



δ(z*-z0*)δ(z+z0)=?
δ(z*+z0*)δ(z-z0)=?

where 'z' is a complex variable 'z0' is a complex number
Formula is just enough, derivation is not needed.
 
Last edited:
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The Dirac delta is a distribution, not a number or a function from one number field to another.
The product of distributions is not in general well defined, see here. You can multiply a distribution by a smooth function, but not in general by another distribution.
So the expressions above do not have a clear meaning. They are not well-defined.
 

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