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Related papers: Hidden symmetries in acoustic wave systems

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We show that for a general system of N s-wave point scatterers, there are always N eigenmodes. These eigenmodes or eigenchannels play the same role as spherical harmonics for a spherically symmetric target--they give a phase shift only. In…

Atomic Physics · Physics 2007-05-23 Sheng Li , Eric J. Heller

Canonical quantum mechanics postulates Hermitian Hamiltonians to ensure real eigenvalues. Counterintuitively, a non-Hermitian Hamiltonian, satisfying combined parity-time (PT) symmetry, could display entirely real spectra above some…

Optics · Physics 2025-01-23 Jianming Wen , Xiaoshun Jiang , Liang Jiang , Min Xiao

We study the symmetric properties of waveguide modes in presence of gain/losses, anisotropy/bianisotropy, or continuous/discrete rotational symmetry. We provide a comprehensive approach to identity the modal symmetry by constructing a…

Optics · Physics 2018-01-24 Zhongfei Xiong , Weijin Chen , Peng Wang , Yuntian Chen

In a power spectrum of the Sun's acoustic waves, the p modes have distinctly skewed frequency profiles. Furthermore, the asymmetry is observed to have the opposite sign in power spectra made from line-of-sight velocity and continuum…

Solar and Stellar Astrophysics · Physics 2011-12-21 Bradley W. Hindman

A system of coupled oscillators on an arbitrary graph is locally driven by the tendency to mutual synchronization between nearby oscillators, but can and often exhibit nonlinear behavior on the whole graph. Understanding such nonlinear…

Dynamical Systems · Mathematics 2023-11-28 Agam Goyal , Zhaoxing Wu , Richard P. Yim , Binhao Chen , Zihong Xu , Hanbaek Lyu

Despite stereo matching accuracy has greatly improved by deep learning in the last few years, recovering sharp boundaries and high-resolution outputs efficiently remains challenging. In this paper, we propose Stereo Mixture Density Networks…

Computer Vision and Pattern Recognition · Computer Science 2021-04-09 Fabio Tosi , Yiyi Liao , Carolin Schmitt , Andreas Geiger

Analytical understanding of how low-dimensional latent features reveal themselves in large-dimensional data is still lacking. We study this by defining a linear latent feature model with additive noise constructed from probabilistic…

Disordered Systems and Neural Networks · Physics 2022-07-20 Philipp Fleig , Ilya Nemenman

In this work, we prove a theorem that states the electromagnetic (EM) duality correspondence between eigenmodes of complementary structures, induces counterpropagating spin-polarized states in different types of waveguides where mirror…

Classical Physics · Physics 2023-06-28 Haddi Ahmadi , Amin Khavasi

We consider the reflection-transmission problem in a waveguide with obstacle. At certain frequencies, for some incident waves, intensity is perfectly transmitted and the reflected field decays exponentially at infinity. In this work, we…

Numerical Analysis · Mathematics 2018-01-29 Anne-Sophie Bonnet-Ben Dhia , Lucas Chesnel , Vincent Pagneux

We experimentally demonstrate PT-symmetric optical lattices with periodical gain and loss profiles in a coherently-prepared four-level N-type atomic system. By appropriately tuning the pertinent atomic parameters, the onset of PT-symmetry…

We present an analysis of enhanced wave transmission through random media with mirror symmetry about a reflecting barrier. The mathematical model is the acoustic wave equation and we consider two setups, where the wave propagation is along…

Mathematical Physics · Physics 2024-01-30 Liliana Borcea , Josselin Garnier

Stereo is a prominent technique to infer dense depth maps from images, and deep learning further pushed forward the state-of-the-art, making end-to-end architectures unrivaled when enough data is available for training. However, deep…

Computer Vision and Pattern Recognition · Computer Science 2019-05-27 Matteo Poggi , Davide Pallotti , Fabio Tosi , Stefano Mattoccia

Embedded solitons are exceptional modes in nonlinear-wave systems with the propagation constant falling in the system's propagation band. An especially challenging topic is seeking for such modes in nonlinear dynamical lattices (discrete…

Pattern Formation and Solitons · Physics 2021-02-17 Hadi Susanto , Boris A. Malomed

Dualities are hidden symmetries that map seemingly unrelated physical systems onto each other. The goal of this work is to systematically construct families of Hamiltonians endowed with a given duality and to provide a universal description…

Applied Physics · Physics 2021-08-26 Michel Fruchart , Claudia Yao , Vincenzo Vitelli

Circumventing the reciprocity invariance has posed an interesting challenge in the design of modern devices for wave engineering. In passive devices, operating the device in the nonlinear response regime is a common means for realizing…

Applied Physics · Physics 2025-10-07 Andrus Giraldo , Behrooz Yousefzadeh

The spectral fluctuations of complex quantum systems, in appropriate limit, are known to be consistent with that obtained from random matrices. However, this relation between the spectral fluctuations of physical systems and random matrices…

Quantum Physics · Physics 2020-09-16 S. Harshini Tekur , M. S. Santhanam

We introduce a sub-symmetry of a differential system as an infinitesimal transformation of a subset of the system that leaves the subset invariant on the solution set of the entire system. We discuss the geometrical meaning and properties…

Mathematical Physics · Physics 2017-05-03 V. Rosenhaus , Ravi Shankar

Implementation of a parity-time (PT) symmetric microwave photonic system in the optical wavelength space with spatial singularity is proposed. In the proposed PT-symmetric microwave photonic system, the gain and loss modes are confined in a…

We implement the concept of complete local symmetry in lossy acoustic waveguides. Despite the presence of losses, the existence of a spatially invariant current is shown theoretically and observed experimentally. We demonstrate how this…

Classical Physics · Physics 2015-08-26 P. A. Kalozoumis , O. Richoux , F. K. Diakonos , G. Theocharis , P. Schmelcher

We develop a new unsupervised symmetry learning method that starts with raw data and provides the minimal generator of an underlying Lie group of symmetries, together with a symmetry-equivariant representation of the data, which turns the…

Machine Learning · Computer Science 2025-07-08 Onur Efe , Arkadas Ozakin