Calculation of the angular momentum of an electromagnetic field inside a waveguide with absolutely conducting walls: ab initio [PDF]
Компьютерная оптика, 2018 In this paper, explicit expressions for the momentum and angular momentum from the Noether's theorem (ab initio) are obtained. These expressions contain squared modules of the coefficients of a guided mode expansion, weighted by the phase singularity ...
Sergey Kharitonov +2 more
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Quantum basic invariants and classical noether’s theorem
, 1993 Taking the generalized time-dependent harmonic oscillator (GTHO) and singular time-dependent harmonic oscillator (STHO) as illustrative examples, we discuss the connection between the quantum basic invariants and classical Noether’s theorem and, for the ...
Gao, Xiao Chun +3 more
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Growth and remodelling from the perspective of Noether’s theorem [PDF]
, 2019 Starting from the observation that the growth of a body breaks the time translation symmetry of the body’s dynamics, we determine a scalar field, called internal time, that defines an indicator of the intrinsic time scale of the growth-related body’s ...
Alfio Grillo +2 more
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Perennial Symmetry Arguments: Aristotle’s Heavenly Cosmology and Noether’s First Theorem [PDF]
, 2019 Attempts to find perennial elements in Aristotle’s cosmology are doomed to failure because his distinction of sub- and supra-lunary realms no longer holds.
Miller, Ryan +2 more
core +1 more source
The classical theory of calculus of variations for generalized functions
Advances in Nonlinear Analysis, 2017 We present an extension of the classical theory of calculus of variations to generalized functions. The framework is the category of generalized smooth functions, which includes Schwartz distributions, while sharing many nonlinear properties with ...
Lecke Alexander +2 more
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Characteristics of Conservation Laws for Difference Equations [PDF]
, 2013 Each conservation law of a given partial differential equation is determined (up to equivalence) by a function known as the characteristic. This function is used to find conservation laws, to prove equivalence between conservation laws, and to prove the ...
Hydon, PE +3 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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Assessment of Gibbs Free Energy Calculation in PI‐Controlled Heating
Chemie Ingenieur Technik, EarlyView.For description and control of chemical processes in lab or industry thermodynamic variable Gibbs free energy provides opportunity to compare and interpret phenomena, even on a quantitative level. In a case study for PI‐controlled heating, impacts on its limits from control delay until parameter quantization are highlighted and assessed.
Jannik Dutschke +4 more
wiley +1 more source
Peskine Sixfolds and Debarre–Voisin Fourfolds With Associated Cubic Fourfolds
Mathematische Nachrichten, EarlyView.ABSTRACT We develop the notion of Peskine sixfolds with associated K3 surfaces and cubic fourfolds and work out numerical conditions for when these associations occur. In discriminant 24, the first family for which there is an associated cubic fourfold, we identify the cubic explicitly.
Corey Brooke +3 more
wiley +1 more source
Conserved momenta of ferromagnetic solitons through the prism of differential geometry
SciPost Physics, 2021 The relation between symmetries and conservation laws for solitons in a ferromagnet is complicated by the presence of gyroscopic (precessional) forces, whose description in the Lagrangian framework involves a background gauge field.
Xingjian Di, Oleg Tchernyshyov
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