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Q: Higher dimensional delta-function from higher dimensional Gaussian

user44690Consider a higher dimensional (or rather multivariate) gaussian $$f(x) = \frac{1}{\sqrt{(2\pi)^n \det{M}}}e^{-\frac{1}{2}x^TM^{-1}x}$$ where $M$ is some matrix. What limit of the above one must take to get some higher dimensional (or multivariate?) delta-function?

 
 
2 hours later…
8:52 AM
A new tag was created. Most likely a typo and it was intended to by ?
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Q: Counting the number of facets of the alternating sign matrix polytopes ($ASM_n$).

ensbanaI’m reading the following definitions and theorem on alternating sign matrices (ASMs). Definition 1. Alternating sign matrices (ASMs) are square matrices with the following properties: entries $\in\{0,1,-1\}$ the entries in each row and column sum to 1 nonzero entries in each row and column alt...

In mathematics, an alternating sign matrix is a square matrix of 0s, 1s, and −1s such that the sum of each row and column is 1 and the nonzero entries in each row and column alternate in sign. These matrices generalize permutation matrices and arise naturally when using Dodgson condensation to compute a determinant. They are also closely related to the six-vertex model with domain wall boundary conditions from statistical mechanics. They were first defined by William Mills, David Robbins, and Howard Rumsey in the former context. == Example == An example of an alternating sign matrix (that is not...
Ignoring the question whether it would be better to discuss the new tag on meta first, I will just point out that the name of the tag you've created probably contains a typo. I suppose you meant alternating rather than altenating. — Martin Sleziak 16 secs ago
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Q: Counting the number of facets of the alternating sign matrix polytopes ($ASM_n$).

ensbanaI’m reading the following definitions and theorem on alternating sign matrices (ASMs). Definition 1. Alternating sign matrices (ASMs) are square matrices with the following properties: entries $\in\{0,1,-1\}$ the entries in each row and column sum to 1 nonzero entries in each row and column alt...

Thanks for commenting. Yes the tag contains a typo. And I’m happy to delete it if it is unlikely to help other users and the site. — ensbana 4 mins ago
 
 
6 hours later…
2:56 PM
A new tag was created.
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Q: Give an $L$-sentence which is true in that structure but false in the other three structures

ZacharyLet $L$ be a language with just one binary function symbol $f$ (which will be interpreted as multiplication). For each item in the list of $L$-structures given below, give an $L$-sentence which is true in that structure but false in the other three. $\mathbb{R}-\{0\}$ with the usual multiplicati...

 

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