Dirac delta function is continuous and differential

In summary, the Dirac delta function is not a literal function, but a limit of functions. It is considered a distribution and is both differentiable and continuous. There are examples of functions that approach the Dirac delta, such as the top hat and gaussian functions, with the gaussian being differentiable while the top hat is not. This concept involves an internal parameter that goes to zero, which is independent of the variable parameter in calculus.
  • #1
astro2cosmos
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since dirac delta function is not a literally a function but a limit of function,does it mean that dirac delta function is continuous and differentiable through out the infinity?
is there any example of dirac delta function if yes then give meeeeeeee?
 
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  • #2
astro2cosmos -> Strictly speaking, the Dirac delta is a distribution, that is it's a functional on the space of smooth and compactly supported functions. As such, one has to be a bit careful as to what does it mean for it to be "differentiable" and "continuous". Still, it is both differentiable and continuous. (I'm sure about differentiability, but have a doubt about continuity...)
is there any example of dirac delta function if yes then give meeeeeeee?
What is that supposed to mean?
 
  • #3
I don't know how to write in latex but examples of dirac delta are the top hat function as the width goes to zero and the (properly normalised) gaussian as the width goes to zero.
 
  • #4
astro2cosmos said:
since dirac delta function is not a literally a function but a limit of function,does it mean that dirac delta function is continuous and differentiable through out the infinity?
is there any example of dirac delta function if yes then give meeeeeeee?

The internal parameter that goes to zero inside the dirac delta is INDEPENDENT of the variable parameter that goes to zero in the calculus process. For any given value of the internal parameter (it is never exactly zero), the dirac delta function is continuous, differentialbe, and integrable as far as calculus is concerned.
 
  • #5
Here's what I learned in my course. There are several functions which in a certain limit approach the dirac delta. The examples I gave are the top hat and the gaussian. The top hat is not differentiable, but the gaussian is. I don't know much more than that.
 

Related to Dirac delta function is continuous and differential

1. What is the Dirac delta function?

The Dirac delta function is a mathematical function that is commonly used in physics and engineering. It is defined as a function that is equal to zero everywhere except at one point, where it is infinitely large. It is often used to represent a point-like distribution of mass or charge.

2. Is the Dirac delta function continuous?

Yes, the Dirac delta function is continuous. It is a function that is defined for all real numbers and has a limit of zero as the variable approaches any point except for the point at which it is equal to infinity. This means that it has no breaks or jumps in its graph and can be drawn without lifting your pencil.

3. Is the Dirac delta function differentiable?

No, the Dirac delta function is not differentiable. This is because it is not a regular function that can be plotted on a graph. It is a distribution, which means that it is defined by its properties rather than by a specific formula. It does not have a well-defined derivative at the point where it is equal to infinity.

4. How is the Dirac delta function used in mathematics?

The Dirac delta function has many applications in mathematics, particularly in the fields of calculus, differential equations, and Fourier analysis. It is often used to simplify calculations and solve problems involving point-like distributions. It is also used as a fundamental tool in the theory of distributions, which extends the concept of a function to include objects like the Dirac delta function.

5. Why is the Dirac delta function important in physics?

The Dirac delta function is important in physics because it allows us to describe and model physical phenomena that involve point-like distributions of mass or charge. It is used in many areas of physics, including quantum mechanics, electromagnetism, and fluid dynamics. Its properties, such as being continuous and not differentiable, make it a useful tool for solving problems and understanding complex systems.

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