The correlation-function tag has no wiki summary.
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Differentiating Propagator, Greens function, Correlation function, etc
For the following quantities respectively, could someone write down the common definitions, their meaning, the field of study in which one would typically find these under their actual name, and most ...
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Why correlation functions?
While this concept is widely used in physics, it is really puzzling (at least for beginners) that you just have to multiply two functions (or the function by itself) at different values of the ...
7
votes
1answer
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Correlation function which has branch cut in momentum space
When correlation function has branch cut in momentum space,
how to find correlation in coordinate space?
For example
$$ \tilde {G}(\omega) = \frac{2i}{\omega+(\omega^2-\nu^2)^{1/2}}$$
How to get the ...
4
votes
1answer
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What are Wightman fields/functions
Simple question: What are Wightman fields? What are Wightman functions?
What are their uses? For example can I use them in operator product expansions? How about in scattering theory?
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How do I define time-ordering for Wightman functions?
This is a follow-up question to What are Wightman fields/functions
Ok, so based on my reading, the field operators of a theory are understood to be operator-valued distributions, that is, to be ...
