We consider the ensemble of $n \times n$ Wigner hermitian matrices
$H = (h_{\ell k})_{1 \leq \ell,k \leq n}$ that generalize the Gaussian unitary ensemble (GUE). The matrix elements $h_{k\ell} = \bar h_{\ell k}$ are given by $h_{\ell k} = n^{-1/2} (x_{\ell k} + \sqrt{-1} y_{\ell k})$, where $x_{\ell k}, y_{\ell k}$ for $1 \leq \ell < k \leq n$ are i.i.d. random variables with mean zero and variance 1/2, $y_{\ell\ell}=0$ and $x_{\ell \ell}$ have mean zero and variance 1. We assume the distribution of $x_{\ell k}, y_{\ell k}$ to have subexponential decay. In a recent paper, four of the authors recently established that the gap distribution and averaged $k$-point correlation of these matrices were \emph{universal} (and in particular, agreed with those for GUE) assuming additional regularity hypotheses on the $x_{\ell k}, y_{\ell k}$. In another recent paper, the other two authors, using a different method, established the same conclusion assuming instead some moment and support conditions on the $x_{\ell k}, y_{\ell k}$. In this short note we observe that the arguments of these two papers can be combined to establish universality of the gap distribution and averaged $k$-point correlations for all Wigner matrices (with subexponentially decaying entries), with no extra assumptions.
[1]
L. Pastur.
On the spectrum of random matrices
,
1972
.
[2]
P. Deift.
Orthogonal Polynomials and Random Matrices: A Riemann-Hilbert Approach
,
2000
.
[3]
S. Péché,et al.
Bulk universality for Wigner matrices
,
2009,
0905.4176.
[4]
H. Yau,et al.
Wegner estimate and level repulsion for Wigner random matrices
,
2008,
0811.2591.
[5]
K. Johansson.
Universality of the Local Spacing Distribution¶in Certain Ensembles of Hermitian Wigner Matrices
,
2000,
math-ph/0006020.