Probabilistic interpretation of Fourier Transform

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The fourier transform is given as below :

$$F(\omega) = \frac{1}{\sqrt{2\pi}} \int^{\infty}_{-\infty} f(t) e^{-i \omega t} \mathrm{d}t$$

Now $$F(\omega) = \frac{1}{\sqrt{2\pi}} \int^{\infty}_{-\infty} f(t) e^{-i \omega t} \mathrm{d}t$$ can be transformed as

$$F(\omega) = 0.5 \frac{1}{\sqrt{2\pi}} \int^{\infty}_{-\infty} k s(k) e^{-i \omega k^2} \mathrm{d}k$$

where $ k = \sqrt{t} $ and $ s(k) = f(t^2) $

The exponential term inside the integral looks like a gaussian distribution although it is a complex function. Is there any connecting probabilistic interpretation along these lines of the fourier transform or series ? Under such an idea a fourier transform would be an expectation of a gaussianish distribution.

Looking forward to insights.

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The characteristic function of a real-valued random variable $X$ is given by

$$\varphi_X (t):=E[e^{itX}],$$

which is an object that completely characterizes the distribution of $X$. If $X$ admits a density function $f$, then $\varphi_X(-t)$ is the Fourier transform of its density function (modulo any differences in a normalizing constant or sign conventions).