Inverse Fourier Transform of |k|^2$\lambda$

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SUMMARY

The discussion centers on the inverse Fourier transform of the function |k|^{2\lambda} e^{ikx}. The integral, represented as ∫_{-\infty}^{\infty} |k|^{2\lambda} e^{ikx} dk, does not converge for any value of λ. Attempts to evaluate the integral by splitting it into two parts and utilizing properties of even and odd functions lead to the conclusion that the integral diverges. Numerical integration methods were suggested as a means to explore the behavior of the integral for various values of λ and x.

PREREQUISITES
  • Understanding of Fourier transforms and their properties
  • Knowledge of complex analysis and convergence of integrals
  • Familiarity with numerical integration techniques
  • Basic concepts of even and odd functions in mathematics
NEXT STEPS
  • Explore the properties of Fourier transforms in relation to convergence
  • Learn numerical integration methods such as Simpson's rule or trapezoidal rule
  • Investigate the implications of different values of λ on the behavior of the integral
  • Study the relationship between even/odd functions and their integrals
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Mathematicians, physics students, and anyone involved in signal processing or applied mathematics who seeks to understand the convergence properties of Fourier transforms.

johnqwertyful
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Homework Statement


[itex]\int_{-\infty}^{\infty} |k|^{2\lambda} e^{ikx} dk[/itex]

Homework Equations


The Attempt at a Solution


As you can guess, this is the inverse Fourier transform of [itex]|k|^{2\lambda}[/itex]. I've tried splitting it from -infinity to 0 and 0 to infinity. I've tried noting that |k| is even, cos is even, sin is odd and getting:

[itex]2\int_0^{\infty} |k|^{2\lambda}\cos(kx)dk[/itex]
But this integral doesn't even converge.
 
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I don't think the original integral converges either, no matter what the value of ##\lambda## is. Try using different values of ##\lambda## and ##x## and integrating numerically with a large interval of integration.
 

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