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This work studies the location estimation problem for a mixture of two rotation invariant log-concave densities. We demonstrate that Least Squares EM, a variant of the EM algorithm, converges to the true location parameter from a randomly…

Machine Learning · Statistics 2019-06-21 Wei Qian , Yuqian Zhang , Yudong Chen

Let $f$ be a Hecke--Maass cuspidal newform of square-free level $N$ and Laplacian eigenvalue $\lambda$. It is shown that $\pnorm{f}_\infty \ll_{\lambda,\epsilon} N^{-1/6}+\epsilon} \pnorm{f}_2$ for any $\epsilon>0$.

Number Theory · Mathematics 2012-07-04 Gergely Harcos , Nicolas Templier

In the class of nonlinear one-parameter real maps we study those with bifurcation that exhibits period doubling cascade. The fixed points of such a map form a finite discrete real set with dimension (2^n)m, where m is the (odd) number of…

Mathematical Physics · Physics 2009-11-11 A. D. Alhaidari

We define a measure of noncompactness $\lambda$ on the standard Hilbert $C^*$-module $l^2(\mathcal A)$ over a unital $C^*$-algebra, such that $\lambda(E)=0$ if and only if $E$ is $\mathcal A$-precompact (i.e.\ it is $\varepsilon$-close to a…

Operator Algebras · Mathematics 2017-11-28 Dragoljub J. Kečkić , Zlatko Lazović

We consider distributional limit of the Pearson chi-square statistic when the number of classes m increases with the sample size n in such way that $n/\sqrt{m} \to {\lambda}$. Under mild moment conditions, the limit is Gaussian for…

Probability · Mathematics 2016-09-13 Grzegorz A. Rempała , Jacek Wesołowski

We have investigated a weighted chi-square distribution of the variable $\xi$ which is a weighted sum of squared normally distributed independent variables whose weights are cosines of angles $\phi_k=2\pi k/N$, where $k \in \{0,1,...,N-1\}$…

Disordered Systems and Neural Networks · Physics 2024-12-24 Vladislav Egorov , Boris Kryzhanovsky

We prove that any $n$-dimensional closed mean convex $\lambda$-hypersurface is convex if $\lambda\le 0.$ This generalizes Guang's work on $2$-dimensional strictly mean convex $\lambda$-hypersurfaces. As a corollary, we obtain a gap theorem…

Differential Geometry · Mathematics 2021-06-21 Tang-Kai Lee

We compare several definitions of the density of a self-bound system, such as a nucleus, in relation with its center-of-mass zero-point motion. A trivial deconvolution relates the internal density to the density defined in the laboratory…

Nuclear Theory · Physics 2007-07-27 B. G. Giraud

We study the isoperimetric problem on $\mathbb{R}^1$ with a prescribed density function $f$ that affects how area and perimeter are measured. We examine density functions that are symmetric, radially increasing, and satisfy two additional…

Metric Geometry · Mathematics 2022-01-07 John Ross

Let f be an $L^2$-normalized weight zero Hecke-Maass cusp form of square-free level N, character $\chi$ and Laplacian eigenvalue $\lambda\geq 1/4$. It is shown that $\| f \|_{\infty} \ll_{\lambda} N^{-1/37}$, from which the hybrid bound…

Number Theory · Mathematics 2015-05-13 Valentin Blomer , Roman Holowinsky

Non-compact three-dimensional QED is studied by computer simulations to understand its chiral symmetry breaking features for N_f>=2, on lattice volumes up to 50^3 and bare masses as low as ma=0.0000625. We compute the chiral condensate,…

High Energy Physics - Lattice · Physics 2009-11-07 S. J. Hands , J. B. Kogut , C. G. Strouthos

We study level number variance in a two-dimensional random matrix model characterized by a power-law decay of the matrix elements. The amplitude of the decay is controlled by the parameter b. We find analytically that at small values of b…

Disordered Systems and Neural Networks · Physics 2015-06-03 A. Ossipov , I. Rushkin , E. Cuevas

In general the kernel of QCD's gap equation possesses a domain of analyticity upon which the equation's solution at nonzero chemical potential is simply obtained from the in-vacuum result through analytic continuation. On this domain the…

Nuclear Theory · Physics 2009-01-01 Huan Chen , Wei Yuan , Lei Chang , Yu-Xin Liu , Thomas Klahn , Craig D. Roberts

By the Pr\'ekopa-Leindler inequality, the difference $X-X'$ has a log-concave density provided that $X$ has a log-concave density and $X, X'$ are independent and identically distributed. We prove that the opposite direction does not always…

Probability · Mathematics 2025-12-30 Min Wang

We use density--functional theory to study the structure of two-dimensional defects inside a circular nematic nanocavity. The density, nematic order parameter, and director fields, as well as the defect core energy and core radius, are…

Soft Condensed Matter · Physics 2010-12-17 D. de las Heras , L. Mederos , E. Velasco

We investigate the statistics of stationary points in the sum of squares of $N$ Gaussian random fields, which we call a "chi-squared" field. The behavior of such a field at a point is investigated, with particular attention paid to the…

Mathematical Physics · Physics 2016-12-13 Jolyon K. Bloomfield , Stephen H. P. Face , Alan H. Guth , Saarik Kalia , Casey Lam , Zander Moss

Overlap fermions, which preserve exact chiral symmetry on the lattice, provide a powerful tool for investigating the topological structure of the vacuum. Applying this formulation to zero-temperature quenched SU(3) configurations generated…

High Energy Physics - Lattice · Physics 2007-05-23 Y. Koma , E. -M. Ilgenfritz , K. Koller , G. Schierholz , T. Streuer , V. Weinberg

The estimation of a log-concave density on $\mathbb{R}$ is a canonical problem in the area of shape-constrained nonparametric inference. We present a Bayesian nonparametric approach to this problem based on an exponentiated Dirichlet…

Statistics Theory · Mathematics 2020-07-14 Ester Mariucci , Kolyan Ray , Botond Szabo

We analyse the $\Gamma$-convergence of general non-local convolution type functionals with varying densities depending on the space variable and on the symmetrized gradient. The limit is a local free-discontinuity functional, where the bulk…

Analysis of PDEs · Mathematics 2024-11-20 Roberta Marziani , Francesco Solombrino

Some properties of $m$-density points and density-degree functions are studied. Moreover the following main results are provided: \vskip2mm \begin{itemize} \item {\it Let $\lambda$ be a continuous differential form of degree $h$ in…

Functional Analysis · Mathematics 2024-07-18 Silvano Delladio