Using fourier and laplace transform to solve PDE

Click For Summary
SUMMARY

The discussion focuses on solving partial differential equations (PDEs), specifically the heat equation, using both Fourier and Laplace transforms. Participants emphasize that the Fourier transform is applied with respect to spatial variables, while the Laplace transform is utilized for temporal variables. This combination leads to a polynomial equation in two variables, facilitating the derivation of a dispersion relation. The conversation highlights the necessity of treating the two transforms independently to achieve accurate solutions.

PREREQUISITES
  • Understanding of partial differential equations (PDEs)
  • Familiarity with Fourier transforms
  • Knowledge of Laplace transforms
  • Basic concepts of dispersion relations in mathematical physics
NEXT STEPS
  • Study the application of Fourier transforms in solving PDEs
  • Learn about Laplace transforms and their role in time-dependent problems
  • Research the derivation of dispersion relations from combined Fourier and Laplace transforms
  • Explore examples of heat equations solved using both transforms
USEFUL FOR

Mathematicians, physicists, and engineering students focusing on applied mathematics, particularly those interested in solving PDEs and understanding the interplay between Fourier and Laplace transforms.

cyw1984
Messages
4
Reaction score
0
PDE is type of heat equation.

Many book only gives an example of solving heat equation using Fourier transform.
An exercise asks me to solve it for using Fourier and laplace transform:

In the heat equation, we'd take the Fourier transform with respect to x for
each term in the equation. How to combine it with using Fourier and laplace transform

Can anyone suggest some example and notes to me??
 
Physics news on Phys.org
umum...the question mention us to use Fourier and laplace transform. Is there mention us to use Fourier transform with respect to t (t>0) and then inverse Fourier transform to solve the solution; Separately, solve the question using laplace transform with respect to x -\infty< x < \infty and then inverse laplace transform?

Can there combines two transformation in one??
What is the result compared with two method??
 
It's all the way around... The Fourier transform is defined in \mathbb{R}, while the Laplace transform is defined in \mathbb{R}^+, so you have to take the Fourier transform in space and the Laplace transform in time. That way, you will land with a polinomial equation in two variables, which will give you some sort of dispersion relation.
 
AiRAVATA said:
It's all the way around... The Fourier transform is defined in \mathbb{R}, while the Laplace transform is defined in \mathbb{R}^+, so you have to take the Fourier transform in space and the Laplace transform in time. That way, you will land with a polinomial equation in two variables, which will give you some sort of dispersion relation.

O...
you mean that it must need to do it independent in two times??

What information will give in this type of question??
 

Similar threads

  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 2 ·
Replies
2
Views
4K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 5 ·
Replies
5
Views
3K
Replies
4
Views
3K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 2 ·
Replies
2
Views
4K
  • · Replies 11 ·
Replies
11
Views
3K
  • · Replies 10 ·
Replies
10
Views
3K