Coherence length of velocity fields

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Apashanka
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I have came across a term "coherence length of velocity field ##\lambda## ",tried to search in the internet but doesn't find any result...will anyone please give a brief summary of this in this context..
 
You'll have to give more context and details. Where exactly did you read this?
 
DrClaude said:
You'll have to give more context and details. Where exactly did you read this?
Okay fine the paper is
https://arxiv.org/abs/1703.08809And the line where I have read this is in the 2nd paragraph
Photo of a printed page of a cosmology paper showing equations A4 and A5 for a quantity Q built from velocity field integrals, followed by a paragraph about symmetry, correlation functions and the vanishing of surface integral contributions.
 
It's very frustrating that they never define what they mean by coherence length.

Typically, coherence length is the distance for which structures in propagating waves can be maintained. That is, if you start a pulse with a specific shape, after the coherence length the pulse will become diffused, its structure lost.

In quantum mechanics, this might also have something to do with quantum decoherence. But in any event, it would have been nice if they would have explained what they meant by the term. In the mean time, a reasonable assumption that they're talking about the exact same thing as explained in this Wikipedia article:
https://en.wikipedia.org/wiki/Coherence_length