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Related papers: Topological Obstructions and How to Avoid Them

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Within the frame of a Group Approach to Quantization anomalies arise in a quite natural way. We present in this talk an analysis of the basic obstructions that can be found when we try to translate symmetries of the Newton equations to the…

High Energy Physics - Theory · Physics 2007-05-23 V. Aldaya , M. Calixto , J. Guerrero

We explain the coarse geometric origin of the fact that certain spectral subspaces of topological insulator Hamiltonians are delocalized, in the sense that they cannot admit an orthonormal basis of localized wavefunctions, with respect to…

Mathematical Physics · Physics 2022-09-23 Matthias Ludewig , Guo Chuan Thiang

Structurally stable (rough) flows on surfaces have only finitely many singularities and finitely many closed orbits, all of which are hyperbolic, and they have no trajectories joining saddle points. The violation of the last property leads…

Dynamical Systems · Mathematics 2017-06-07 Vladislav Kruglov , Dmitry Malyshev , Olga Pochinka

Training a large multilayer neural network can present many difficulties due to the large number of useless stationary points. These points usually attract the minimization algorithm used during the training phase, which therefore results…

Optimization and Control · Mathematics 2021-06-14 Alberto De Santis , Giampaolo Liuzzi , Stefano Lucidi , Edoardo Maria Tronci

This work deals with the presence of topological structures in models of two real scalar fields in the two-dimensional spacetime. The subject concerns the presence of a geometric constriction, which appears with a modification of the…

High Energy Physics - Theory · Physics 2024-03-11 D. Bazeia , M. A. Feitosa , R. Menezes , G. S. Santiago

Positional encodings enable Transformers to incorporate sequential information, yet their theoretical understanding remains limited to two properties: distance attenuation and translation invariance. Because natural language lacks purely…

Machine Learning · Computer Science 2026-02-11 Zihan Gu , Ruoyu Chen , Han Zhang , Hua Zhang , Yue Hu

Providing generalization guarantees for stochastic optimization algorithms remains a key challenge in learning theory. Recently, numerous works demonstrated the impact of the geometric properties of optimization trajectories on…

Machine Learning · Computer Science 2026-01-23 Mario Tuci , Lennart Bastian , Benjamin Dupuis , Nassir Navab , Tolga Birdal , Umut Şimşekli

A common problem in the optimization of structures is the handling of uncertainties in the parameters. If the parameters appear in the constraints, the uncertainties can lead to an infinite number of constraints. Usually the constraints…

Optimization and Control · Mathematics 2012-05-01 Daniel P. Mohr , Ina Stein , Thomas Matzies , Christina A. Knapek

A key challenge in machine learning is to explain how learning dynamics select among the many solutions that achieve identical loss values in overparameterized models - a phenomenon known as implicit bias. Controlling this bias provides a…

Machine Learning · Computer Science 2026-04-07 Nicola Aladrah , Emanuele Ballarin , Matteo Biagetti , Alessio Ansuini , Alberto d'Onofrio , Fabio Anselmi

Understanding the optimization dynamics of neural networks is necessary for closing the gap between theory and practice. Stochastic first-order optimization algorithms are known to efficiently locate favorable minima in deep neural…

Machine Learning · Computer Science 2023-06-22 Charles Guille-Escuret , Hiroki Naganuma , Kilian Fatras , Ioannis Mitliagkas

Graphs are ubiquitous data structures for representing interactions between entities. With an emphasis on the use of graphs to represent chemical molecules, we explore the task of learning to generate graphs that conform to a distribution…

Machine Learning · Computer Science 2019-03-08 Qi Liu , Miltiadis Allamanis , Marc Brockschmidt , Alexander L. Gaunt

Placement is crucial in the physical design, as it greatly affects power, performance, and area metrics. Recent advancements in analytical methods, such as DREAMPlace, have demonstrated impressive performance in global placement. However,…

Machine Learning · Computer Science 2024-02-29 Ke Xue , Xi Lin , Yunqi Shi , Shixiong Kai , Siyuan Xu , Chao Qian

A surrogate-based topology optimisation algorithm for linear elastic structures under parametric loads and boundary conditions is proposed. Instead of learning the parametric solution of the state (and adjoint) problems or the optimisation…

Numerical Analysis · Mathematics 2025-11-04 Matteo Giacomini , Antonio Huerta

We test the hypothesis that the microscopic temporal structure of near-field turbulence downstream of a sudden contraction contains geometry-identifiable information pertaining to the shape of the upstream obstruction. We measure a set of…

Fluid Dynamics · Physics 2024-12-17 Mukesh Karunanethy , Raghunathan Rengaswamy , Mahesh V Panchagnula

The area of topology optimization of continuum structures of which is allowed to change in order to improve the performance is now dominated by methods that employ the material distribution concept. The typical methods of the topology…

Computational Engineering, Finance, and Science · Computer Science 2013-09-24 Jun-ichi Koga , Jiro Koga , Shunji Homma

Generative modeling is typically framed as learning mapping rules, but from an observer's perspective without access to these rules, the task becomes disentangling the geometric support from the probability distribution. We propose that…

Machine Learning · Statistics 2025-12-04 Rui Tong

Complex networks, which are the abstractions of many real-world systems, present a persistent challenge across disciplines for people to decipher their underlying information. Recently, hyperbolic geometry of latent spaces has gained…

Social and Information Networks · Computer Science 2024-05-28 Kai Zheng , Qilong Feng , Yaohang Li , Qichang Zhao , Jinhui Xu , Jianxin Wang

We study cohomological obstructions to the existence of global conserved quantities. In particular, we show that, if a given local variational problem is supposed to admit global solutions, certain cohomology classes cannot appear as…

Mathematical Physics · Physics 2015-10-30 M. Francaviglia , M. Palese , E. Winterroth

Ordinal Embedding places n objects into R^d based on comparisons such as "a is closer to b than c." Current optimization-based approaches suffer from scalability problems and an abundance of low quality local optima. We instead consider a…

Computational Geometry · Computer Science 2018-05-22 Jesse Anderton , Virgil Pavlu , Javed Aslam

This paper addresses the problem of a boundary control design for traffic evolving in a large-scale urban network. The traffic state is described on a macroscopic scale and corresponds to the vehicle density, whose dynamics are governed by…

Optimization and Control · Mathematics 2021-03-17 Liudmila Tumash , Carlos Canudas-de-Wit , Maria Laura Delle Monache