Results 31 to 40 of about 262,520 (170)

Compact Manifolds With Unbounded Nilpotent Fundamental Groups and Positive Ricci Curvature

Communications on Pure and Applied Mathematics, EarlyView.
ABSTRACT It follows from the work of Kapovitch and Wilking that a closed manifold with nonnegative Ricci curvature has a uniformly almost nilpotent fundamental group. Leftover questions and conjectures, have asked if in this context the fundamental group is actually uniformly almost abelian. The main goal of this work is to construct examples (Mk9,gk)$(
Elia Bruè, Aaron Naber, Daniele Semola
wiley   +1 more source

Renormalization group-like proof of the universality of the Tutte polynomial for matroids [PDF]

Discrete Mathematics & Theoretical Computer Science, 2013
In this paper we give a new proof of the universality of the Tutte polynomial for matroids. This proof uses appropriate characters of Hopf algebra of matroids, algebra introduced by Schmitt (1994). We show that these Hopf algebra characters are solutions
G. Duchamp, N. Hoang-Nghia, Thomas Krajewski, A. Tanasa   +3 more
doaj   +1 more source

Nonconstant Positive Steady States for a Predator–Prey System With Signal‐Dependent Diffusion

Mathematische Nachrichten, EarlyView.
ABSTRACT This paper investigates a highly nonlinear predator–prey reaction–diffusion system featuring signal‐dependent prey diffusion, where the motility of the prey is modulated by a chemical signal released by predators. For unbounded functional responses, we establish the global‐in‐time existence and uniform‐in‐time boundedness of classical ...
Qigang Deng, Hao Shen, Ranchao Wu, Hao Wang   +3 more
wiley   +1 more source

Álgebras de Hopf trançadas [PDF]

, 2013
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas, Programa de Pós-Graduação em Matemática Pura e Aplicada, Florianópolis, 2013Álgebras de Nichols são ferramentas importantes para a classificação de
Pinter, Sara Regina da Rosa
core  

Spectral Submanifolds of Delay Systems: Control in Continuous and Discrete Time

International Journal of Robust and Nonlinear Control, EarlyView.
ABSTRACT This paper presents both continuous‐time and discretization‐based approaches for constructing spectral submanifolds (SSMs) for time delay systems. The continuous‐time approach built upon sun–star calculus, reformulates the governing delay differential equation (DDE) as an operator differential equation (OpDE).
Bence Szaksz, Gábor Orosz, Gábor Stépán   +2 more
wiley   +1 more source

Ore Extensions for the Sweedler’s Hopf Algebra H4

, 2020
The aim of this paper is to classify all Hopf algebra structures on the quotient of Ore extensions H4[z;σ] of automorphism type for the Sweedler′s 4-dimensional Hopf algebra H4.
Shilin Yang, Yongfeng Zhang
core   +1 more source

Hexapod Locomotion Across Structured and Unstructured Terrains: A Data‐Driven Review of Modeling, Control, and Validation

Journal of Field Robotics, EarlyView.
ABSTRACT The design of a hexapod is complex and requires integration between kinematic models, control systems, and sensing. Existing literature has reviewed these sub‐systems in isolation. Since 2021, there has been no review of the field despite significant advancements in soft soil, lunar traversal, and artificial intelligence.
Akhil Rampersad, Bashan Naidoo
wiley   +1 more source

Fermionic quantization of Hopf solitons [PDF]

, 2006
In this paper we show how to quantize Hopf solitons using the Finkelstein-Rubinstein approach. Hopf solitons can be quantized as fermions if their Hopf charge is odd.
Speight, J.Martin, Krusch, Steffen
core   +1 more source

Capital‐Labour Substitution in Macroeconomics: A Survey of Mechanisms, Dynamics and Policy Insights

Journal of Economic Surveys, EarlyView.
ABSTRACT Macroeconomic conclusions often hinge on a single, hard‐to‐pin‐down parameter: the elasticity of substitution between capital and labour, σ. This survey synthesises theory and evidence on how results change once we move beyond the Cobb–Douglas benchmark (σ=1$\sigma = 1$).
Francisco Rebelo, Fernando Del Río
wiley   +1 more source

Extensões de álgebras obtidas a partir de álgebras de Hopf [PDF]

, 2012
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas, Programa de Pós-graduação em Matemática e Computação Científica, Florianópolis, 2011Neste trabalho fazemos uma descrição completa do grupo quântico
Teixeira, Mateus Medeiros
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