Fourier phase (unwrapping problem)

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    Fourier Phase
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The discussion centers on the Fourier transform of an integrable function and the associated phase function, which often experiences discontinuities as it wraps from -π to π. The main inquiry is about the conditions or theorems that ensure the phase function remains continuous. While algorithms exist to recover a continuous phase, the original poster seeks a definitive answer regarding the mathematical guarantees for continuity based on properties of the function f. The referenced material does not adequately address this specific question about continuity conditions. Understanding these conditions is crucial for applications in signal processing and related fields.
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Hello,
given an integrable function f(x), and its Fourier transform

\mathcal{F}\{f\}(\omega)=\int_{\mathbb{R}}f(x)e^{-i\omega x}dx,

we consider the phase \mathrm{Ph}_f : \mathbb{R}\rightarrow [-\pi,\pi) which is given by:

\mathrm{Ph}_f (\omega) = \mathrm{arg}(\mathcal{F}\{f\}(\omega))

In general the phase function will have discontinuities (when it wraps from -\pi to \pi, and there are algorithms that attempts to recover a continuous phase function.
My question is: why should the phase be a continuous function? What is the condition/theorem that guarantees that the phase is always continuous?
 
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I am afraid that chapter doesn't answer my question which was:

"...Is there a condition on f (or a theorem) that guarantees that the phase is certainly continuous? ..."
 
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