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How to solve, or at least how to proceed to solve, the following equation for $g(u)$

$$\int_0^{\infty} \{1-\cos(2\pi uh)\} g(u)du = (1+h^{\alpha})^{\beta/\alpha} -1?$$

Here $0<\alpha\leq2$ and $-\infty<\beta\leq2$. Any help will be greatly appreciated!

Edit: By following the suggestion in the comment, first I differentiate with respect to $h$ to get $$\int_0^{\infty} \sin(2\pi uh)2\pi u g(u) du = \beta (1+h^{\alpha})^{\beta/\alpha-1} h^{\alpha-1}.$$ Now taking inverse sine Fourier transform gives $$g(u) = \frac{c}{u}\int\limits_0^{\infty}\sin(2\pi uh)(1+h^{\alpha})^{\beta/\alpha-1}h^{\alpha-1}dh,$$ where $c$ is a suitable constant. But, if I am not wrong, $\sin(2\pi uh)(1+h^{\alpha})^{\beta/\alpha-1}h^{\alpha-1}$ is not integrable for all $\alpha$ and $\beta$. Am I making some mistake?

Why do I expect a solution for $g$ of the above equation?: I am trying to find the spectral measure (which exists) of a generalized covaiance function of the form $c\{1-(1+h^{\alpha})^{\beta/\alpha}\}$ using the relation $K(h) = \int\limits_0^{\infty} \{\cos(2\pi uh)-1\}F(du)$ from this paper, equation 3.

How to solve, or at least how to proceed to solve, the following equation for $g(u)$

$$\int_0^{\infty} \{1-\cos(2\pi uh)\} g(u)du = (1+h^{\alpha})^{\beta/\alpha} -1?$$

Here $0<\alpha\leq2$ and $-\infty<\beta\leq2$. Any help will be greatly appreciated!

Edit: By following the suggestion in the comment, first I differentiate with respect to $h$ to get $$\int_0^{\infty} \sin(2\pi uh)2\pi u g(u) du = \beta (1+h^{\alpha})^{\beta/\alpha-1} h^{\alpha-1}.$$ Now taking inverse sine Fourier transform gives $$g(u) = \frac{c}{u}\int\limits_0^{\infty}\sin(2\pi uh)(1+h^{\alpha})^{\beta/\alpha-1}h^{\alpha-1}dh,$$ where $c$ is a suitable constant. But, if I am not wrong, $\sin(2\pi uh)(1+h^{\alpha})^{\beta/\alpha-1}h^{\alpha-1}$ is not integrable for all $\alpha$ and $\beta$. Am I making some mistake?

How to solve, or at least how to proceed to solve, the following equation for $g(u)$

$$\int_0^{\infty} \{1-\cos(2\pi uh)\} g(u)du = (1+h^{\alpha})^{\beta/\alpha} -1?$$

Here $0<\alpha\leq2$ and $-\infty<\beta\leq2$. Any help will be greatly appreciated!

Edit: By following the suggestion in the comment, first I differentiate with respect to $h$ to get $$\int_0^{\infty} \sin(2\pi uh)2\pi u g(u) du = \beta (1+h^{\alpha})^{\beta/\alpha-1} h^{\alpha-1}.$$ Now taking inverse sine Fourier transform gives $$g(u) = \frac{c}{u}\int\limits_0^{\infty}\sin(2\pi uh)(1+h^{\alpha})^{\beta/\alpha-1}h^{\alpha-1}dh,$$ where $c$ is a suitable constant. But, if I am not wrong, $\sin(2\pi uh)(1+h^{\alpha})^{\beta/\alpha-1}h^{\alpha-1}$ is not integrable for all $\alpha$ and $\beta$. Am I making some mistake?

Why do I expect a solution for $g$ of the above equation?: I am trying to find the spectral measure (which exists) of a generalized covaiance function of the form $c\{1-(1+h^{\alpha})^{\beta/\alpha}\}$ using the relation $K(h) = \int\limits_0^{\infty} \{\cos(2\pi uh)-1\}F(du)$ from this paper, equation 3.

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Shanks
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  • 9

How to solve, or at least how to proceed to solve, the following equation for $g(u)$

$$\int_0^{\infty} \{1-\cos(2\pi uh)\} g(u)du = (1+h^{\alpha})^{\beta/\alpha} -1?$$

Here $0<\alpha\leq2$ and $-\infty<\beta\leq2$. Any help will be greatly appreciated!

Edit: By following the suggestion in the comment, first I differentiate with respect to $h$ to get $$\int_0^{\infty} \sin(2\pi uh)2\pi u g(u) du = \beta (1+h^{\alpha})^{\beta/\alpha-1} h^{\alpha-1}.$$ Now taking inverse sine Fourier transform gives $$g(u) = \frac{c}{u}\int\limits_0^{\infty}\sin(2\pi uh)(1+h^{\alpha})^{\beta/\alpha-1}h^{\alpha-1}dh,$$ where $c$ is a suitable constant. But, if I am not wrong, $\sin(2\pi uh)(1+h^{\alpha})^{\beta/\alpha-1}h^{\alpha-1}$ is not integrable for all $\alpha$ and $\beta$. Am I making some mistake?

How to solve, or at least how to proceed to solve, the following equation for $g(u)$

$$\int_0^{\infty} \{1-\cos(2\pi uh)\} g(u)du = (1+h^{\alpha})^{\beta/\alpha} -1?$$

Any help will be greatly appreciated!

How to solve, or at least how to proceed to solve, the following equation for $g(u)$

$$\int_0^{\infty} \{1-\cos(2\pi uh)\} g(u)du = (1+h^{\alpha})^{\beta/\alpha} -1?$$

Here $0<\alpha\leq2$ and $-\infty<\beta\leq2$. Any help will be greatly appreciated!

Edit: By following the suggestion in the comment, first I differentiate with respect to $h$ to get $$\int_0^{\infty} \sin(2\pi uh)2\pi u g(u) du = \beta (1+h^{\alpha})^{\beta/\alpha-1} h^{\alpha-1}.$$ Now taking inverse sine Fourier transform gives $$g(u) = \frac{c}{u}\int\limits_0^{\infty}\sin(2\pi uh)(1+h^{\alpha})^{\beta/\alpha-1}h^{\alpha-1}dh,$$ where $c$ is a suitable constant. But, if I am not wrong, $\sin(2\pi uh)(1+h^{\alpha})^{\beta/\alpha-1}h^{\alpha-1}$ is not integrable for all $\alpha$ and $\beta$. Am I making some mistake?

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Shanks
  • 133
  • 9

Solving an equation of function

How to solve, or at least how to proceed to solve, the following equation for $g(u)$

$$\int_0^{\infty} \{1-\cos(2\pi uh)\} g(u)du = (1+h^{\alpha})^{\beta/\alpha} -1?$$

Any help will be greatly appreciated!