Integral of dirac delta function at x=0

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Discussion Overview

The discussion revolves around the integral of the Dirac delta function, specifically whether the expression Integral(delta(0)) equals 1 when evaluated from negative infinity to positive infinity. Participants explore the definition and properties of the delta function in relation to this integral.

Discussion Character

  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants assert that Integral(delta(0)) = 1 is correct, interpreting the delta function's properties as leading to this conclusion.
  • Others clarify that the delta function is not a conventional function and argue that evaluating it at x=0 to write delta(0) is not valid.
  • A participant emphasizes that the correct expression should be Integral(delta(x)) from -infinity to +infinity, which equals 1, rather than Integral(delta(0)).
  • There is a suggestion that the expression Integral(delta(0)) is meaningless, thus not equal to 1.

Areas of Agreement / Disagreement

Participants express differing views on the validity of evaluating the delta function at zero and the meaning of the integral involving delta(0). No consensus is reached regarding the correctness of the initial claim.

Contextual Notes

Participants highlight the distinction between the delta function as a distribution and its evaluation at specific points, indicating potential misunderstandings about its properties.

vsravani
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Hi

Can somebody help me with this...
Is is correct to say that, Integral(delta(0)) = 1 (limits are from -infinity to +infinity)
I don't know latex and sorry for the inconvenience in readability.

Thanks,
VS
 
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Yes.
 
vsravani said:
Hi

Can somebody help me with this...
Is is correct to say that, Integral(delta(0)) = 1 (limits are from -infinity to +infinity)
I don't know latex and sorry for the inconvenience in readability.

Thanks,
VS
Examine the definition of the delta function. You will see that yes is the obvious answer.
 
vsravani said:
Hi

Can somebody help me with this...
Is is correct to say that, Integral(delta(0)) = 1 (limits are from -infinity to +infinity)
I don't know latex and sorry for the inconvenience in readability.

Thanks,
VS

The [tex]\delta(x)[/tex] is not a function, so you can't evaluate it at [tex]x=0[/tex] and write [tex]\delta(0)[/tex]. Maybe you meant

[tex]\int_{-\infty}^{+\infty}\delta(x)dx=1[/tex]

this is correct. Instead

[tex]\int_{-\infty}^{+\infty}\delta(0)dx[/tex]

is meaningless, so in particular it's not 1.
 

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