Results 1 to 10 of about 16,555,400 (192)
First post-Newtonian <i>N</i>-body problem in Einstein-Cartan theory with the Weyssenhoff fluid: Lagrangian and first integrals. [PDF]
Eur Phys J C Part Fields, 2023 The rotational dynamics of an N -body system at the first post-Newtonian order in Einstein–Cartan theory is derived. This result is achieved by performing the point-particle limit of the equations of motion of the Weyssenhoff fluid, which models the ...
Battista E, De Falco V, Usseglio D.
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Charged Shear-Free Fluids and Complexity in First Integrals [PDF]
Entropy, 2022 The equation yxx=f(x)y2+g(x)y3 is the charged generalization of the Emden-Fowler equation that is crucial in the study of spherically symmetric shear-free spacetimes.
Sfundo C. Gumede +2 more
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First Integrals of Shear-Free Fluids and Complexity [PDF]
Entropy, 2021 A single master equation governs the behaviour of shear-free neutral perfect fluid distributions arising in gravity theories. In this paper, we study the integrability of yxx=f(x)y2, find new solutions, and generate a new first integral.
Sfundo C. Gumede +2 more
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Comparison of Different Approaches to Construct First Integrals for Ordinary Differential Equations
Abstract and Applied Analysis, 2014 Different approaches to construct first integrals for ordinary differential equations and systems of ordinary differential equations are studied here. These approaches can be grouped into three categories: direct methods, Lagrangian or partial Lagrangian
Rehana Naz +2 more
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Existence of global symmetries of divergence-free fields with first integrals [PDF]
Journal of Mathematics and Physics, 2023 The relationship between symmetry fields and first integrals of divergence-free vector fields is explored in three dimensions in light of its relevance to plasma physics and magnetic confinement fusion.
D. Perrella +2 more
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First Integrals and Symmetries of Nonholonomic Systems [PDF]
Archive for Rational Mechanics and Analysis, 2021 In nonholonomic mechanics, the presence of constraints in the velocities breaks the well-understood link between symmetries and first integrals of holonomic systems, expressed by Noether’s Theorem.
P. Balseiro, N. Sansonetto
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Higher order first integrals of autonomous dynamical systems [PDF]
Journal of Geometry and Physics, 2021 A theorem is derived which determines higher order first integrals of autonomous holonomic dynamical systems in a general space, provided the collineations and the Killing tensors -- up to the order of the first integral -- of the kinetic metric, defined
Antonios Mitsopoulos, M. Tsamparlis
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Solutions for Multitime Reaction–Diffusion PDE
Mathematics, 2022 A previous paper by our research group introduced the nonlinear multitime reaction–diffusion PDE (with oblique derivative) as a generalized version of the single-time model.
Cristian Ghiu, Constantin Udriste
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Integrability and Limit Cycles via First Integrals
Symmetry, 2021 In many problems appearing in applied mathematics in the nonlinear ordinary differential systems, as in physics, chemist, economics, etc., if we have a differential system on a manifold of dimension, two of them having a first integral, then its phase ...
J. Llibre
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Invariant Algebraic Curves of Generalized Liénard Polynomial Differential Systems
Mathematics, 2022 In this study, we focus on invariant algebraic curves of generalized Liénard polynomial differential systems x′=y, y′=−fm(x)y−gn(x), where the degrees of the polynomials f and g are m and n, respectively, and we correct some results previously stated.
Jaume Giné, Jaume Llibre
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