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Let $S$ be a punctured Riemann surface with Euler characteristic $\chi(S)<0$. For any unitary representation $\rho: \pi_1(S) \to U(N)$, we introduce its renormalized energy and its harmonic representatives, which are equivariant harmonic…

Differential Geometry · Mathematics 2025-08-29 Antoine Song

Let $f(x)$, $x\in\mathbb R^2$, be a piecewise smooth function with a jump discontinuity across a smooth surface $\mathcal S$. Let $f_{\Lambda\epsilon}$ denote the Lambda tomography (LT) reconstruction of $f$ from its discrete Radon data…

Numerical Analysis · Mathematics 2020-12-30 Alexander Katsevich

Let $D_j\subset\Bbb C^{n_j}$ be a pseudoconvex domain and let $A_j\subset D_j$ be a locally pluriregular set, $j=1,...,N$. Put $$ X:=\bigcup_{j=1}^N A_1\times...\times A_{j-1}\times D_j\times A_{j+1}\times ...\times A_N\subset\Bbb…

Complex Variables · Mathematics 2007-05-23 Marek Jarnicki , Peter Pflug

Limitations on bandwidth and power consumption impose strict bounds on data rates of diagnostic imaging systems. Consequently, the design of suitable (i.e. task- and data-aware) compression and reconstruction techniques has attracted…

Image and Video Processing · Electrical Eng. & Systems 2021-01-26 Iris A. M. Huijben , Bastiaan S. Veeling , Kees Janse , Massimo Mischi , Ruud J. G. van Sloun

We develop a unified approach for establishing rates of decay for the Fourier transform of a wide class of dynamically defined measures. Among the key features of the method is the systematic use of the $L^2$-flattening theorem obtained in…

Dynamical Systems · Mathematics 2024-12-23 Simon Baker , Osama Khalil , Tuomas Sahlsten

Continuing the analysis in a unified scheme for treating generalized superselection sectors based upon the notion of selection criteria for states of relevance in quantum physics, we extend the Doplicher-Roberts superselection theory for…

Mathematical Physics · Physics 2007-05-23 I. Ojima

R. Kaufman and M. Tsujii proved that the Fourier transform of self-similar measures has a power decay outside of a sparse set of frequencies. We present a version of this result for homogeneous self-similar measures, with quantitative…

Classical Analysis and ODEs · Mathematics 2020-01-31 Carolina A. Mosquera , Pablo Shmerkin

Differential equations may possess coefficients that vary on a spectrum of scales. Because coefficients are typically multiplicative in real space, they turn into convolution operators in spectral space, mixing all wavenumbers. However, in…

Numerical Analysis · Mathematics 2016-04-20 Shravan Hanasoge

We use world-line methods for pseudo-supersymmetry to construct $sl(2|1)$-invariant actions for the $(2,2,0)$ chiral and ($1,2,1)$ real supermultiplets of the twisted $D$-module representations of the $sl(2|1)$ superalgebra. The derived…

High Energy Physics - Theory · Physics 2016-02-16 L. Baulieu , N. L. Holanda , F. Toppan

Functional Spectral Imaging (FSI) models image formation as the recovery of tissue surrogates such as density and stiffness from spectral perturbations of a self-adjoint elliptic operator. Rather than relying on reflectivity or relaxation…

Medical Physics · Physics 2025-10-21 Cesar Mello Fernando Medina da Cunha

We analyze signal recovery when samples are taken concomitantly from a signal and its Fourier transform. This two-sided sampling framework extends classical one-sided reconstruction and is particularly useful when measurements in either…

Signal Processing · Electrical Eng. & Systems 2026-03-18 Mert Kayaalp , Oleg Szehr

We study holographic pseudoentropy for subregions in non-unitary Euclidean conformal field theories (CFTs) within the framework of the de Sitter/conformal field theory (dS/CFT) correspondence. Pseudoentropy, defined as the von Neumann…

High Energy Physics - Theory · Physics 2026-05-28 Giorgos Anastasiou , Ignacio J. Araya , Avijit Das , Javier Moreno

In this work we investigate the computation of dispersion relation (i.e., band functions) for three-dimensional photonic crystals, formulated as a parameterized Maxwell eigenvalue problem, using a novel hp-adaptive sampling algorithm. We…

Numerical Analysis · Mathematics 2024-06-18 Yueqi Wang , Richard Craster , Guanglian Li

We establish a general uniqueness theorem for subharmonic functions of several variables on a domain. A corollary from this uniqueness theorem for holomorphic functions is formulated in terms of the zero subset of holomorphic functions and…

Complex Variables · Mathematics 2016-06-14 Bulat Khabibullin , Nargiza Tamindarova

In this paper we prove a uniform Fourier restriction estimate over the class of simple curves where the last coordinate function can be extended to a holomorphic function of bounded frequency in a sufficiently large disc. The proof is based…

Classical Analysis and ODEs · Mathematics 2023-03-31 Jaume de Dios Pont , Helge Jørgen Samuelsen

We give new formulas for finding a compactly supported function $v$ on $\mathbb{R}^d$, $d\geq 1$, from its Fourier transform $\mathcal{F} v$ given within the ball $B_r$. For the one-dimensional case, these formulas are based on the theory…

Classical Analysis and ODEs · Mathematics 2021-07-19 Mikhail Isaev , Roman G. Novikov

We study the reduced symplectic cohomology of disk subbundles in negative symplectic line bundles. We show that this cohomology theory "sees" the spectrum of a quantum action on quantum cohomology. Precisely, quantum cohomology decomposes…

Symplectic Geometry · Mathematics 2020-03-19 Sara Venkatesh

We explore quantitative descriptors that herald when a many-particle system in $d$-dimensional Euclidean space $\mathbb{R}^d$ approaches a hyperuniform state as a function of the relevant control parameter. We establish quantitative…

Soft Condensed Matter · Physics 2021-05-26 Salvatore Torquato

We establish second main theorems for holomorphic curves into a projective subvary $V \subset \mathbb{P}^n(\mathbb{C})$ of dimension $k$, intersecting hypersurfaces in $N$-subgeneral position with respect to $V$ $(N > k)$. Our results…

Complex Variables · Mathematics 2026-05-11 Si Duc Quang , Nguyen Van An , Tran An Hai

We examine how the square-integrable function subspaces are transformed using the holomorphic Fourier transform. On account of this, the extended Paley-Wiener theorem over the Hardy-Sobolev spaces is produced. The theorem also asserts that…

Functional Analysis · Mathematics 2024-03-19 Detian Liu , Haichou Li , Kit Ian Kou