Most general form of nascent delta function

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Discussion Overview

The discussion centers around the search for a general formula for nascent delta functions, specifically exploring the conditions under which a function or functional approaches the delta function as a limit. The scope includes theoretical aspects of distributions and their properties, as well as potential applications in engineering contexts.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant seeks a general elegant formula for nascent delta functions, expressing frustration with the existing random forms.
  • Another participant clarifies that the delta function is a distribution rather than a conventional function, suggesting a related thread for further reading.
  • A participant specifies interest in a function g(x,y) that approaches the delta function as x approaches 0, while also wanting to understand g(x,y) in other contexts.
  • One participant proposes that the solution involves a linear combination of probability distributions, noting that both the normal and Cauchy distributions satisfy the limit condition but questioning the existence of other distributions that do as well.
  • Another participant asserts that the Dirac delta is not unique and that many distributions can converge to it, but notes the lack of a classification system for such distributions.

Areas of Agreement / Disagreement

Participants express differing views on the nature and classification of nascent delta functions, with no consensus on a general formula or the number of distributions that can satisfy the limit condition.

Contextual Notes

The discussion highlights limitations in the understanding of nascent delta functions, particularly regarding the number of distributions that can converge to the delta function and the lack of constraints on the form of g(x,y).

mmzaj
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Dear all

I'm wondering if you can help me find the most general formula of all nascent delta functions. all i have found a somewhat random forms . I'm looking for a general elegant formula that all the forms can be derived from .

thanks in advance .
 
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thanks a lot , really informative , but here is the thing , I'm looking for a function ( or a functional ) g such that :

lim x ->0 g (x,y) = delta(y).

well , obviously any nascent delta function satisfies the condition , but the problem is that I am also interested in g(x,y) every where , not only when x -> 0 , and there is no constrains on g(x,y) other than it equals delta when x->0 . hence , the program is to find the most general form of the nascent delta functions , and construct a linear combination of them . i tried Fourier series and transform to check if there are common properties of the nascent delta functions in the frequency domain - as we electrical engineers like to call it - but in vain . here is the dilemma . can you help me here .

thanks in advance .
 
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now , after a long struggle i found that what I'm looking for isn't any thing but a linear combination of probability distributions ( such as the normal distribution ) G (x,y) such that lim x->0 G(x,y) = delta (y) . but again , there is no information about the number of distributions that satisfy that condition . the normal distribution does , cauchy distribution does , but are there other distributions like that ?
 
The Dirac delta is not special; it's just another point in the space of distributions. There are exactly as many things that converge to the zero distribution as there are that converge to the Dirac delta distribution.

There really isn't a classification for things that converge to the Dirac delta other than "it converges to the Dirac delta".
 

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