I What does the product part of Laughlin wave function mean?

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The discussion centers on the interpretation of the product term in the Laughlin wave function, specifically the notation $$\prod_{j<k}^{N}\left(z_j-z_k\right)^q$$. Participants clarify that the lower index indicates a product over pairs of indices where j is less than k, and there is no upper limit on k. The expression can be rewritten as a nested product, confirming that for N=3, it simplifies to $$\left(z_1-z_2\right)^q\left(z_1-z_3\right)^q\left(z_2-z_3\right)^q$$. The discussion emphasizes understanding the structure of the product to grasp the wave function's meaning. Overall, clarity on the notation is crucial for interpreting the Laughlin wave function correctly.
George Keeling
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confused by product symbol with two subscripts
I am looking at the Laughlin wave function and it contains the term
$$\prod_{j<k}^{N}\left(z_j-z_k\right)^q$$
In Wikipedia the lower index on ##\Pi## is ##1\le i<j\le N## and there is no upper index. I'm not sure what either mean. For example would
$$\prod_{j<k}^{N}\left(z_j-z_k\right)^q=\prod_{k=2}^{N}\left[\prod_{j=1}^{k-1}\left(z_j-z_k\right)^q\right]?$$
(It seems that ##k## cannot be 1 because there would be nothing to multiply in the second product). I'm not sure what else the expression could mean.

For ##N=3## that would give ##\ \left(z_1-z_2\right)^q\left(z_1-z_3\right)^q\left(z_2-z_3\right)^q## I think.
 
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Yes, this is the meaning of that product symbol with two subscripts.
 
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