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Related papers: John Equation Constraints for the 3D X-ray Transfo…

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The use of geometric methods has proved useful in the hamiltonian description of classical constrained systems. In this note we provide the first steps toward the description of the geometry of quantum constrained systems. We make use of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Alejandro Corichi

The Johnson-Lindenstrauss (JL) lemma is a cornerstone of dimensionality reduction in Euclidean space, but its applicability to non-Euclidean data has remained limited. This paper extends the JL lemma beyond Euclidean geometry to handle…

Data Structures and Algorithms · Computer Science 2025-10-28 Chengyuan Deng , Jie Gao , Kevin Lu , Feng Luo , Cheng Xin

Models describing one- and two-photon transitions for ions in crystalline environments are unified and extended to the case of parity-allowed and parity- forbidden p-photon transitions. The number of independent parameters for…

Atomic and Molecular Clusters · Physics 2015-06-26 M. Kibler , M. Daoud

The core theme of X-ray crystallography is reconstructing the electron density distribution of crystals under the constraints of observed diffraction data. Nevertheless, the reconstruction of electron density distribution by straightforward…

Materials Science · Physics 2015-07-14 Hui Li , Meng He , Ze Zhang

The mathematical formalism necessary for the diagramatic evaluation of quantum corrections to a conformally invariant field theory for a self-interacting scalar field on a curved manifold with boundary is considered. The evaluation of…

High Energy Physics - Theory · Physics 2009-11-07 George Tsoupros

The famous theorem of Fritz John states that any convex body has a unique maximal volume inscribed ellipsoid, known as the John Ellipsoid. Computing the John Ellipsoid is a fundamental problem in convex optimization. In this paper, we focus…

Data Structures and Algorithms · Computer Science 2025-10-29 Yang Cao , Xiaoyu Li , Zhao Song , Xin Yang , Tianyi Zhou

We describe examples of drastic truncations of conformal bootstrap equations encoding much more information than that obtained by a direct numerical approach. A three-term truncation of the four point function of a free scalar in any space…

High Energy Physics - Theory · Physics 2016-11-23 Ferdinando Gliozzi

While the proposal of the Tri-plane representation has advanced the development of the 3D-aware image generative models, problems rooted in its inherent structure, such as multi-face artifacts caused by sharing the same features in…

Computer Vision and Pattern Recognition · Computer Science 2025-07-22 Ru Jia , Xiaozhuang Ma , Jianji Wang , Nanning Zheng

X-ray tomography is a powerful volumetric imaging technique, but detailed three dimensional (3D) imaging requires the acquisition of a large number of individual X-ray images, which is time consuming. For applications where spatial…

Image and Video Processing · Electrical Eng. & Systems 2023-02-28 Zhenduo Shang , Thomas Blumensath

Consider a polynomial optimization problem. Adding polynomial equations generated by the Fritz John conditions to the constraint set does not change the optimal value. As proved in [arXiv:2205.04254 (2022)], the objective polynomial has…

Optimization and Control · Mathematics 2022-11-15 Ngoc Hoang Anh Mai

Full 3D estimation of human pose from a single image remains a challenging task despite many recent advances. In this paper, we explore the hypothesis that strong prior information about scene geometry can be used to improve pose estimation…

Computer Vision and Pattern Recognition · Computer Science 2021-12-10 Zhe Wang , Liyan Chen , Shaurya Rathore , Daeyun Shin , Charless Fowlkes

Symmetry postulates play a crucial role in various approaches to reconstruct quantum theory from a few basic principles. Discrete and continuous symmetries are under consideration. The continuous case better matches the physical needs for…

Quantum Physics · Physics 2025-12-19 Gerd Niestegge

We propose a new formulation for 3+1 numerical relativity, based on a constrained scheme and a generalization of Dirac gauge to spherical coordinates. This is made possible thanks to the introduction of a flat 3-metric on the spatial…

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. Bonazzola , E. Gourgoulhon , P. Grandclement , J. Novak

This paper explores possibilities for new uses of the Radon transform for imaging and analysis of lightfields. We show that the previously reported Dimansionality Gap can be derived from an ultrahyperbolic PDE, first proposed by F. John,…

Image and Video Processing · Electrical Eng. & Systems 2019-07-03 Todor Georgiev , He Qin , Haotian Li

Resolving sources beyond the diffraction limit is important in imaging, communications, and metrology. Current image-based methods of super-resolution require phase information (either of the source points or an added filter) and perfect…

Optics · Physics 2025-12-16 S. A. Wadood , Shaurya Aarav , Kevin Liang , Jason W Fleischer

This paper presents three quantitative sampling methods for reconstructing extended sources of the biharmonic wave equation using scattered field data. The first method employs an indicator function that solely relies on scattered fields $…

Mathematical Physics · Physics 2025-12-12 Xiaodong Liu , Qingxiang Shi , Jing Wang

Conformal field theories (CFTs) with cubic global symmetry in 3D are relevant in a variety of condensed matter systems and have been studied extensively with the use of perturbative methods like the $\varepsilon$ expansion. In an earlier…

High Energy Physics - Theory · Physics 2020-06-10 Stefanos R. Kousvos , Andreas Stergiou

Conformal field theories have been long known to describe the fascinating universal physics of scale invariant critical points. They describe continuous phase transitions in fluids, magnets, and numerous other materials, while at the same…

High Energy Physics - Theory · Physics 2019-04-18 David Poland , Slava Rychkov , Alessandro Vichi

Linear convergence of first-order methods is typically characterized by global optimization conditions whose constants reflect worst-case geometry of the ambient space. In high-dimensional or structured problems, these global constants can…

Optimization and Control · Mathematics 2026-04-21 Faris Chaudhry , Anthea Monod , Keisuke Yano

Computed tomography is a method for synthesizing volumetric or cross-sectional images of an object from a collection of projections. Popular reconstruction methods for computed tomography are based on idealized models and assumptions that…

Numerical Analysis · Mathematics 2022-03-03 Frederik H. Pedersen , Jakob S. Jørgensen , Martin S. Andersen