Search Results
Search type | Search syntax |
---|---|
Tags | [tag] |
Exact | "words here" |
Author |
user:1234 user:me (yours) |
Score |
score:3 (3+) score:0 (none) |
Answers |
answers:3 (3+) answers:0 (none) isaccepted:yes hasaccepted:no inquestion:1234 |
Views | views:250 |
Code | code:"if (foo != bar)" |
Sections |
title:apples body:"apples oranges" |
URL | url:"*.example.com" |
Saves | in:saves |
Status |
closed:yes duplicate:no migrated:no wiki:no |
Types |
is:question is:answer |
Exclude |
-[tag] -apples |
For more details on advanced search visit our help page |
Statistics of spectral properties of matrix-valued random variables.
1
vote
Eigenvectors of random unitary matrices
The crucial point is that the eigenvectors are not unique, as David Handelman commented. There is a gauge freedom since you can change their phase at will. If you want the map $U\to(D,V)$ to be biject …
0
votes
Sum of Square of the Eigenvalues of Wishart Matrix
The joint probability distribution of the eigenvalues of $S$ is proportional to
$$ \rho(S)=e^{-{\rm Tr}(S)}\det(S)^{a/2}|\Delta(S)|,$$
where $a=m-d-1$ and $\Delta(S)$ is the Vandermonde. The average v …
6
votes
Fourier transform of eigenvalue distribution of GUE matrices
Complementing the answer by Carlo, if you take all $k$'s equal you have
$$f_{\rm GUE(d)}(k,...,k)\propto \int dX e^{ik{\rm Tr}(X)}e^{-\frac{d}{2}{\rm Tr}(X^2)}.$$
Taking $x$ to be any real diagonal el …
1
vote
Spectral gap of $AA^{T}$ for Bernoulli random matrix A
The spectrum of random matrices has some universality properties, in the sense that they do not depend on details of the distribution of the matrix elements. For instance, the spectral gap, i.e. the s …
11
votes
What is the Katz-Sarnak philosophy?
I do not know what is exactly the KS philosophy, or much number theory for that matter, but maybe I can tell you a few things. Take the Riemann zeta function, for instance. It was discovered by Montgo …
2
votes
Non combinatorial random matrix theory
I think this text by Eynard, Kimura and Ribault may interest you. There are some of those diagrams in chapter 2, but there are also nice connections to algebraic geometry, loop equations and integrabl …
7
votes
Accepted
Expected value of the largest singular value of a random matrix with entries in $N (0,1)$
If $A$ is a Gaussian random matrix as you describe, then the ensemble of matrices given by $A^TA$ is known as the Wishart ensemble, or the Laguerre ensemble. It has been extensively studied, and you c …
7
votes
Accepted
Are random circulant matrices almost orthonormal?
The diagonal elements of $P=\frac{1}{N}MM^T$, like
$$P_{11}=\frac{1}{N}\sum_{i=1}^NX_i^2,$$
satisfy $ \langle P_{11}\rangle=1$ and $ \langle P_{11}^2\rangle=1+2/N$ (variance decreases like $N^{-1}$).
…
0
votes
Probability of positive definiteness of a random matrix
I think the following papers are closely related to what you are looking for:
How many eigenvalues of a Gaussian random matrix are positive? (2011)
Index Distribution of Gaussian Random Matrices (20 …
8
votes
Advanced reference and roadmap about random matrices theory
The Oxford handbook of random matrix theory (Oxford University Press, 2011), edited by G. Akemann, J. Baik, P. Di Francesco, is an excellent reference, which covers a wide variety of properties and ap …
7
votes
Moments of the trace of orthogonal matrices
I am writing more than a year after the question was posted, only to spell out some more details regarding the calculation implicit in the solution presented by Suvrit, and to clarify the dependence o …
1
vote
Normalizing Entries In Defining Random Matrices (Wigner Matrix)
On the one hand, you can compute the average of the trace of $X^2$ by using the eigenvalues, $\langle {\rm Tr}(X^2)\rangle=\sum_{i}\langle \lambda_{i}\rangle$. If the eigenvalues must be $O(1)$, this …
1
vote
A Gaussian integral over complex variables by a defined Green's function for a Gaussian ense...
Your first expression for the potential
$$ \Phi(\omega)=\frac{1}{N}\log E_J \int d^2z...$$
is equivalent to
$$ e^{N\Phi(\omega)}=E_J \int d^2z...$$
Ok?
Writing the expectation in $J$ according to it …
3
votes
Accepted
A question from Zeitouni's Introduction to Random Matrices
I think the essence is the central limit theorem. If you compute the traces of powers of your random matrix, they will be the sum of many independent random variables and will be Gaussian distributed …
1
vote
Accepted
Alternative formula of a Green's function for average density of eigenvalues of random matrix
I'll post an answer to spell out all the details.
You have $$G(ω)=\frac{1}{N}E\left[{\rm Tr}\frac{1}{Iω−J}\right]=\frac{1}{N}E\left[\sum_\lambda\frac{1}{ω−\lambda}\right]$$
This can be written as $$ …