Skip to main content

All Questions

18 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
21 votes
0 answers
2k views

The Fourier Transform of taking Eigenvalues

The purpose of this question is to ask about the Fourier transform of the map which associate to an $n$ by $n$ matrix its $n$ eigenvalues, or some function of the $n$ eigenvalues. The main motivation ...
Gil Kalai's user avatar
  • 24.7k
5 votes
0 answers
133 views

Expectation of a specific random variable on the probability space of $n\times n$ matrices over $\{0,1\}$

Let $\mathcal{G}_{n,\frac{1}{2}}$ be the probability space of $n\times n$ matrices over $\{0,1\}$ and each entry of the matrix is independently equal to 1 with probability $\frac{1}{2}$ and equal to 0 ...
user173856's user avatar
  • 1,997
5 votes
0 answers
327 views

Eigenvalues of Random Regular Bipartite Graphs

I am looking for a way of getting a good estimate of the eigenvalues of random bipartite d-regular graphs. The literature has very precise values the proofs of which are very involved and since I am ...
user1189053's user avatar
4 votes
0 answers
355 views

Distribution of min/max row sum of matrix with i.i.d. uniform random variables

Given a $n\times n$ symmetric random matrix such that all diagonal elements are all fixed as $1$. all elements in upper triangle (excluding the diagonal) are i.i.d. uniform random variables ...
Tony's user avatar
  • 272
3 votes
0 answers
151 views

Largest eigenvalue divided by $n$

Let $X$ be an $n\times n$ symmetric random matrix whose diagonal is fixed as $1$, and every element in the upper triangle (excluding the diagonal) is drawn from Bernoulli($p$). The elements in the ...
Tony's user avatar
  • 272
3 votes
0 answers
414 views

Eigenvalue distribution of a special symmetric matrix of uniform random variables

Given a $n\times n$ symmetric random matrix such that all diagonal elements are all fixed as $0$. all other elements in the upper triangle are uniform random variables over $[0,1]$. all ...
Tony's user avatar
  • 272
3 votes
0 answers
436 views

Rank of Hadamard product with random matrices

I do research in statistics and am not sure whether the following is considered research level or not in mathematics. If it isn't, I'm happy because that means the answer is probably known and I can ...
KOE's user avatar
  • 131
2 votes
0 answers
106 views

The distribution of eigenvalues of linear combinations of random unitary matrices

Suppose that $\alpha_{1},\dots,\alpha_{r}$ are non-zero complex numbers. Let $U_{1},\dots,U_{r}$ be random $n\times n$-unitary matrices. Let $A=\alpha_{1}U_{1}+\dots+\alpha_{r}U_{r}$. I have observed ...
Joseph Van Name's user avatar
2 votes
0 answers
95 views

Maximum volume submatrices of a Khatri-Rao product of matrix exponentials

My question requires quite a bit of setup, which leads to a conjecture. So I split my question into three parts, Setup, Conjecture, and Question. Setup: Pick any two right stochastic matrices $\...
Jandré Snyman's user avatar
2 votes
0 answers
64 views

Largest eigenvalue of two types of slightly different random matrices

Consider two types of slightly different $n \times n$ symmetric random matrices $X$. The diagonal elements of $X$ are fixed as $1$. Suppose $\frac{k}{n} \to \alpha$ for some constant $\alpha\in(0,1)$. ...
Tony's user avatar
  • 272
2 votes
0 answers
59 views

Min/max row-sum distribution of a symmetric matrix of uniform random variables over $[0,1]$ and fixed $1$s along diagonal and scattered $1$s

Given a $n\times n$ symmetric random matrix such that all diagonal elements are all fixed as $0$. randomly select $k$ distinct cells in the upper triangle (excluding the diagonal), and then ...
Tony's user avatar
  • 272
2 votes
0 answers
102 views

Eigenvalue distribution for a real-valued random matrix with correlated Gaussian entries

I'm working on an application where I would greatly benefit from knowing the distributions of the eigenvalues of a real-valued random matrix whose elements can be assumed to be Gaussian, but where I ...
Ian Cero's user avatar
  • 121
2 votes
0 answers
322 views

Expectation of square root of positive definite matrix

Let $U$ be a random matrix, supported on the positive-definite cone of matrices. We denote $\sqrt{U}$ to be the principal square root of $U$. That is, the unique positive-definite matrix such that $\...
Cain's user avatar
  • 393
2 votes
0 answers
458 views

Random variable matrix exponential

I am trying to find out the distribution of a matrix exponential which is a function of a random variable. My mathematics background is very limited and I hope I can receive some help from here. What ...
Winton's user avatar
  • 21
1 vote
0 answers
80 views

Moments from characteristic function for matrices

When $x$ is a random variable with the smooth characteristic function $\phi_x(t) = \mathbb{E}e^{itx}$, we can easily compute the moments as $\mathbb{E}[x^k] = i^{-n}\phi_x^{(n)}(0)$. There is no magic ...
user3826143's user avatar
1 vote
0 answers
225 views

Distribution and expectation of inverse of a random Bernoulli matrix

This question cropped up as a part of my research. Let us assume a $n\times n$ random matrix $\mathbf{M}$ with elements iid distributed to a Bernoulli distribution that takes values $\{0,1\}$ with ...
Nishant Singh's user avatar
0 votes
0 answers
45 views

On full rank submatrices of a construction

Take two matrices $T_1$ and $T_2$ in $\mathbb Z^{n\times n}$ with entries uniformly in $[-b,b]\cap\mathbb Z$ at some $b>0$. The matrices will be of rank $n$ each with probability at least $1-\frac1{...
VS.'s user avatar
  • 1,826
0 votes
0 answers
47 views

"Probability" for a partitioned matrix to be singular

Let $A,B\in\mathbb{R}^{n\times n}$ be two nonsingular matrices with $A\ne B$, and consider the following partitioned matrix $$ M:=\begin{bmatrix}AA^\top + BB^\top & A^\top \Delta_1 A + B^\top \...
Ludwig's user avatar
  • 2,712