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Related papers: Time-Dependent Lagrangian Biomechanics

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Phenotypic evolution implies sequential fixations of new genomic sequences. The speed at which these mutations fixate depends, in part, on the relative fitness (selection coefficient) of the mutant vs. the ancestor. Using a simple…

Populations and Evolution · Quantitative Biology 2014-02-04 Sorin Tanase-Nicola , Ilya Nemenman

In this paper we study the reductions of evolutionary PDEs on the manifold of the stationary points of time-dependent symmetries. In particular we describe how the finite dimensional Hamiltonian structure of the reduced system is obtained…

solv-int · Physics 2007-05-23 Monica Ugaglia

This paper introduces a linear state-space model with time-varying dynamics. The time dependency is obtained by forming the state dynamics matrix as a time-varying linear combination of a set of matrices. The time dependency of the weights…

Machine Learning · Statistics 2014-10-06 Jaakko Luttinen , Tapani Raiko , Alexander Ilin

In this paper we propose a process of Lagrangian reduction and reconstruction for symmetric discrete-time mechanical systems acted on by external forces, where the symmetry group action on the configuration manifold turns it into a…

Differential Geometry · Mathematics 2023-08-30 Matías I. Caruso , Javier Fernández , Cora Tori , Marcela Zuccalli

Time-dependent potentials are common in galactic systems that undergo significant evolution, interactions, or encounters with other galaxies, or when there are dynamic processes like star formation and merging events. Recent studies show…

Astrophysics of Galaxies · Physics 2025-02-04 Eduárd Illés , Dániel Jánosi , Tamás Kovács

The problem of biped locomotion at steady speeds is discussed through a Lagrangian formulation developed for velocity-dependent, body driving forces. Human walking on a level surface is analyzed in terms of the data on the resultant…

Biological Physics · Physics 2013-05-29 Valery B. Kokshenev

We describe how geometrical methods can be applied to a system with explicitly time-dependent second-class constraints so as to cast it in Hamiltonian form on its physical phase space. Examples of particular interest are systems which…

High Energy Physics - Theory · Physics 2007-05-23 Jonathan M. Evans , Philip A. Tuckey

In this paper, we will analyze a time dependent geometry in a massive theory of gravity. This will be done by analyzing Vaidya space-time in such a massive theory of gravity. As gravitational collapse is a time dependent system, we will…

We analyze the dynamical equations obeyed by a classical system with position-dependent mass. It is shown that there is a non-conservative force quadratic in the velocity associated to the variable mass. We construct the Lagrangian and the…

Mathematical Physics · Physics 2013-01-18 Sara Cruz y Cruz , Oscar Rosas-Ortiz

In this study, firstly, the k-th order extension of complex product manifold is consid- ered. Then the higher order vertical, complete lifts of geometric structures on product manifold to its extended spaces are given. Also higher order…

Dynamical Systems · Mathematics 2009-03-03 Mehmet Tekkoyun

This talk discusses various aspects of the structure of space-time presenting mechanisms leading to the explanation of the "rigidity" of the manifold and to the emergence of time, i.e. of the Lorentzian signature. The proposed ingredient is…

General Relativity and Quantum Cosmology · Physics 2017-03-22 Angelo Tartaglia

We present the fully general time-dependent multiconfiguration self-consistent-field method to describe the dynamics of a system consisting of arbitrary different kinds and numbers of interacting fermions and bosons. The total wave function…

Atomic Physics · Physics 2017-10-11 Ryoji Anzaki , Takeshi Sato , Kenichi L. Ishikawa

Diffeomorphism-induced symmetry transformations and time evolution are distinct operations in generally covariant theories formulated in phase space. Time is not frozen. Diffeomorphism invariants are consequently not necessarily constants…

General Relativity and Quantum Cosmology · Physics 2009-11-11 J. M. Pons , D. C. Salisbury

We develop the theory of discrete time Lagrangian mechanics on Lie groups, originated in the work of Veselov and Moser, and the theory of Lagrangian reduction in the discrete time setting. The results thus obtained are applied to the…

solv-int · Physics 2009-10-31 A. I. Bobenko , Yu. B. Suris

In this thesis we revise the concept of phase space in modern physics and devise a way to explicitly incorporate physical dimension into geometric mechanics. A historical account of metrology and phase space is given to illustrate the…

Differential Geometry · Mathematics 2019-10-21 Carlos Zapata-Carratala

The global time is defined in covariant form under the condition of a constant mean curvature slicing of spacetime. The background static metric is taken in the tangent space. The global intrinsic time is identified with the logarithmic…

General Relativity and Quantum Cosmology · Physics 2018-04-23 A. B. Arbuzov , A. E. Pavlov

Newtonian physics is describes macro-objects sufficiently well, however it does not describe microobjects. A model of Extended Mechanics for Quantum Theory is based on an axiomatic generalization of Newtonian classical laws to arbitrary…

Classical Physics · Physics 2013-07-11 Timur F. Kamalov

The decay process of the schematic one-dimensional three-body system is considered. A time-dependent approach is used in combination with a one-dimensional three-body model, which is composed of a heavier core nucleus and two nucleons, with…

Nuclear Theory · Physics 2018-04-12 Tomohiro Oishi , Lorenzo Fortunato

4-dim intrinsic (material) Riemannian metric $G$ of the material 4-D space-time continuum $P$ is utilized as the characteristic of the aging processes developing in the material. Manifested through variation of basic material…

Mathematical Physics · Physics 2016-09-07 A. Chudnovsky , S. Preston

We define a time-dependent extension of the quantum geometric tensor to describe the geometry of the time-parameter space for a quantum state, by considering small variations in both time and wave function parameters. Compared to the…

Quantum Physics · Physics 2025-02-05 Bogar Díaz , Diego Gonzalez , Marcos J. Hernández , J. David Vergara