PHYS3001 Classical Mechanics
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Variational Formulation of Fluid and Geophysical Fluid Dynamics
Advances in Geophysical and Environmental Mechanics and Mathematics Gualtiero Badin Fulvio Crisciani Variational Formulation of Fluid and Geophysical Fluid Dynamics Mechanics, Symmetries and Conservation Laws Advances in Geophysical and Environmental Mechanics and Mathematics Series editor Holger Steeb, Institute of Applied Mechanics (CE), University of Stuttgart, Stuttgart, Germany More information about this series at http://www.springer.com/series/7540 Gualtiero Badin • Fulvio Crisciani Variational Formulation of Fluid and Geophysical Fluid Dynamics Mechanics, Symmetries and Conservation Laws 123 Gualtiero Badin Fulvio Crisciani Universität Hamburg University of Trieste Hamburg Trieste Germany Italy ISSN 1866-8348 ISSN 1866-8356 (electronic) Advances in Geophysical and Environmental Mechanics and Mathematics ISBN 978-3-319-59694-5 ISBN 978-3-319-59695-2 (eBook) DOI 10.1007/978-3-319-59695-2 Library of Congress Control Number: 2017949166 © Springer International Publishing AG 2018 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. -
Chapter 2 Introduction to Electrostatics
Chapter 2 Introduction to electrostatics 2.1 Coulomb and Gauss’ Laws We will restrict our discussion to the case of static electric and magnetic fields in a homogeneous, isotropic medium. In this case the electric field satisfies the two equations, Eq. 1.59a with a time independent charge density and Eq. 1.77 with a time independent magnetic flux density, D (r)= ρ (r) , (1.59a) ∇ · 0 E (r)=0. (1.77) ∇ × Because we are working with static fields in a homogeneous, isotropic medium the constituent equation is D (r)=εE (r) . (1.78) Note : D is sometimes written : (1.78b) D = ²oE + P .... SI units D = E +4πP in Gaussian units in these cases ε = [1+4πP/E] Gaussian The solution of Eq. 1.59 is 1 ρ0 (r0)(r r0) 3 D (r)= − d r0 + D0 (r) , SI units (1.79) 4π r r 3 ZZZ | − 0| with D0 (r)=0 ∇ · If we are seeking the contribution of the charge density, ρ0 (r) , to the electric displacement vector then D0 (r)=0. The given charge density generates the electric field 1 ρ0 (r0)(r r0) 3 E (r)= − d r0 SI units (1.80) 4πε r r 3 ZZZ | − 0| 18 Section 2.2 The electric or scalar potential 2.2 TheelectricorscalarpotentialFaraday’s law with static fields, Eq. 1.77, is automatically satisfied by any electric field E(r) which is given by E (r)= φ (r) (1.81) −∇ The function φ (r) is the scalar potential for the electric field. It is also possible to obtain the difference in the values of the scalar potential at two points by integrating the tangent component of the electric field along any path connecting the two points E (r) d` = φ (r) d` (1.82) − path · path ∇ · ra rb ra rb Z → Z → ∂φ(r) ∂φ(r) ∂φ(r) = dx + dy + dz path ∂x ∂y ∂z ra rb Z → · ¸ = dφ (r)=φ (rb) φ (ra) path − ra rb Z → The result obtained in Eq. -
Calculus of Variations in the Convex Case : an Introduction to Fathi's
Calculus of variations in the convex case : an introduction to Fathi’s weak KAM theorem and Mather’s theory of minimal invariant measures Alain Chenciner, Barcelona july 2004 1st lecture. Calculus of variations in the convex case (local struc- tures). From Euler-Lagrange equations to the Poincar´e-Cartan integral invariant, the Legendre transform and Hamilton’s equations. Exercices. Flows, differential forms, symplectic structures 2nd lecture. The Hamilton-Jacobi equation. The solutions of Hamilton’s equations as characteristics. Lagrangian sub- manifolds and geometric solutions of the Hamilton-Jacobi equation. Caus- tics as an obstruction to the existence of global solutions to the Cauchy problem. Exercices. The geodesic flow on a torus of revolution as an example of a completely integrable system 3rd lecture. Minimizers. Weierstrass theory of minimizers. Minimizing KAM tori, Existence of min- imizers (Tonelli’s theorem) and the Lax-Oleinik semi-group. Exercices. Examples around the pendulum 4th lecture. Global solutions of the Hamilton-Jacobi equation Weak KAM solutions as fixed points of the Lax-Oleinik semi-group; con- vergence of the semi-group in the autonomous case. Conjugate weak KAM solutions. Exercices. Burger’s equation and viscosity solutions. 5th lecture. Mather’s theory. Class A geodesics and minimizing mea- sures. The α and β functions as a kind of integrable skeleton Exercices. The time-periodic case as a generalization of Aubry-Mather the- ory, Birkhoff billiards, Hedlund’s example in higher dimension. 1 1st lecture. Calculus of variations in the convex case (local struc- tures). General convexity hypotheses. M = TI n = IRn/ZZ n is the n-dimen- sional torus (the theory works with an arbitrary compact manifold but the torus will allow us to work with global coordinates). -
1 the Basic Set-Up 2 Poisson Brackets
MATHEMATICS 7302 (Analytical Dynamics) YEAR 2016–2017, TERM 2 HANDOUT #12: THE HAMILTONIAN APPROACH TO MECHANICS These notes are intended to be read as a supplement to the handout from Gregory, Classical Mechanics, Chapter 14. 1 The basic set-up I assume that you have already studied Gregory, Sections 14.1–14.4. The following is intended only as a succinct summary. We are considering a system whose equations of motion are written in Hamiltonian form. This means that: 1. The phase space of the system is parametrized by canonical coordinates q =(q1,...,qn) and p =(p1,...,pn). 2. We are given a Hamiltonian function H(q, p, t). 3. The dynamics of the system is given by Hamilton’s equations of motion ∂H q˙i = (1a) ∂pi ∂H p˙i = − (1b) ∂qi for i =1,...,n. In these notes we will consider some deeper aspects of Hamiltonian dynamics. 2 Poisson brackets Let us start by considering an arbitrary function f(q, p, t). Then its time evolution is given by n df ∂f ∂f ∂f = q˙ + p˙ + (2a) dt ∂q i ∂p i ∂t i=1 i i X n ∂f ∂H ∂f ∂H ∂f = − + (2b) ∂q ∂p ∂p ∂q ∂t i=1 i i i i X 1 where the first equality used the definition of total time derivative together with the chain rule, and the second equality used Hamilton’s equations of motion. The formula (2b) suggests that we make a more general definition. Let f(q, p, t) and g(q, p, t) be any two functions; we then define their Poisson bracket {f,g} to be n def ∂f ∂g ∂f ∂g {f,g} = − . -
Hamilton Description of Plasmas and Other Models of Matter: Structure and Applications I
Hamilton description of plasmas and other models of matter: structure and applications I P. J. Morrison Department of Physics and Institute for Fusion Studies The University of Texas at Austin [email protected] http://www.ph.utexas.edu/ morrison/ ∼ MSRI August 20, 2018 Survey Hamiltonian systems that describe matter: particles, fluids, plasmas, e.g., magnetofluids, kinetic theories, . Hamilton description of plasmas and other models of matter: structure and applications I P. J. Morrison Department of Physics and Institute for Fusion Studies The University of Texas at Austin [email protected] http://www.ph.utexas.edu/ morrison/ ∼ MSRI August 20, 2018 Survey Hamiltonian systems that describe matter: particles, fluids, plasmas, e.g., magnetofluids, kinetic theories, . \Hamiltonian systems .... are the basis of physics." M. Gutzwiller Coarse Outline William Rowan Hamilton (August 4, 1805 - September 2, 1865) I. Today: Finite-dimensional systems. Particles etc. ODEs II. Tomorrow: Infinite-dimensional systems. Hamiltonian field theories. PDEs Why Hamiltonian? Beauty, Teleology, . : Still a good reason! • 20th Century framework for physics: Fluids, Plasmas, etc. too. • Symmetries and Conservation Laws: energy-momentum . • Generality: do one problem do all. • ) Approximation: perturbation theory, averaging, . 1 function. • Stability: built-in principle, Lagrange-Dirichlet, δW ,.... • Beacon: -dim KAM theorem? Krein with Cont. Spec.? • 9 1 Numerical Methods: structure preserving algorithms: • symplectic, conservative, Poisson integrators, -
2 Classical Field Theory
2 Classical Field Theory In what follows we will consider rather general field theories. The only guiding principles that we will use in constructing these theories are (a) symmetries and (b) a generalized Least Action Principle. 2.1 Relativistic Invariance Before we saw three examples of relativistic wave equations. They are Maxwell’s equations for classical electromagnetism, the Klein-Gordon and Dirac equations. Maxwell’s equations govern the dynamics of a vector field, the vector potentials Aµ(x) = (A0, A~), whereas the Klein-Gordon equation describes excitations of a scalar field φ(x) and the Dirac equation governs the behavior of the four- component spinor field ψα(x)(α =0, 1, 2, 3). Each one of these fields transforms in a very definite way under the group of Lorentz transformations, the Lorentz group. The Lorentz group is defined as a group of linear transformations Λ of Minkowski space-time onto itself Λ : such that M M→M ′µ µ ν x =Λν x (1) The space-time components of Λ are the Lorentz boosts which relate inertial reference frames moving at relative velocity ~v. Thus, Lorentz boosts along the x1-axis have the familiar form x0 + vx1/c x0′ = 1 v2/c2 − x1 + vx0/c x1′ = p 1 v2/c2 − 2′ 2 x = xp x3′ = x3 (2) where x0 = ct, x1 = x, x2 = y and x3 = z (note: these are components, not powers!). If we use the notation γ = (1 v2/c2)−1/2 cosh α, we can write the Lorentz boost as a matrix: − ≡ x0′ cosh α sinh α 0 0 x0 x1′ sinh α cosh α 0 0 x1 = (3) x2′ 0 0 10 x2 x3′ 0 0 01 x3 The space components of Λ are conventional three-dimensional rotations R. -
Electromagnetic Fields and Energy
MIT OpenCourseWare http://ocw.mit.edu Haus, Hermann A., and James R. Melcher. Electromagnetic Fields and Energy. Englewood Cliffs, NJ: Prentice-Hall, 1989. ISBN: 9780132490207. Please use the following citation format: Haus, Hermann A., and James R. Melcher, Electromagnetic Fields and Energy. (Massachusetts Institute of Technology: MIT OpenCourseWare). http://ocw.mit.edu (accessed [Date]). License: Creative Commons Attribution-NonCommercial-Share Alike. Also available from Prentice-Hall: Englewood Cliffs, NJ, 1989. ISBN: 9780132490207. Note: Please use the actual date you accessed this material in your citation. For more information about citing these materials or our Terms of Use, visit: http://ocw.mit.edu/terms 8 MAGNETOQUASISTATIC FIELDS: SUPERPOSITION INTEGRAL AND BOUNDARY VALUE POINTS OF VIEW 8.0 INTRODUCTION MQS Fields: Superposition Integral and Boundary Value Views We now follow the study of electroquasistatics with that of magnetoquasistat ics. In terms of the flow of ideas summarized in Fig. 1.0.1, we have completed the EQS column to the left. Starting from the top of the MQS column on the right, recall from Chap. 3 that the laws of primary interest are Amp`ere’s law (with the displacement current density neglected) and the magnetic flux continuity law (Table 3.6.1). � × H = J (1) � · µoH = 0 (2) These laws have associated with them continuity conditions at interfaces. If the in terface carries a surface current density K, then the continuity condition associated with (1) is (1.4.16) n × (Ha − Hb) = K (3) and the continuity condition associated with (2) is (1.7.6). a b n · (µoH − µoH ) = 0 (4) In the absence of magnetizable materials, these laws determine the magnetic field intensity H given its source, the current density J. -
NONLINEAR DISPERSIVE WAVE PROBLEMS Thesis by Jon
NONLINEAR DISPERSIVE WAVE PROBLEMS Thesis by Jon Christian Luke In Partial Fulfillment of the Requirements For the Degree of Doctor of Philosophy California Institute of Technology Pasadena, California 1966 (Submitted April 4, 1966) -ii ACKNOWLEDGMENTS The author expresses his thanks to Professor G. B. Whitham, who suggested the problems treated in this dissertation, and has made available various preliminary calculations, preprints of papers, and lectur~ notes. In addition, Professor Whitham has given freely of his time for useful and enlightening discussions and has offered timely advice, encourageme.nt, and patient super vision. Others who have assisted the author by suggestions or con structive criticism are Mr. G. W. Bluman and Mr. R. Seliger of the California Institute of Technology and Professor J. Moser of New York University. The author gratefully acknowledges the National Science Foundation Graduate Fellowship that made possible his graduate education. J. C. L. -iii ABSTRACT The nonlinear partial differential equations for dispersive waves have special solutions representing uniform wavetrains. An expansion procedure is developed for slowly varying wavetrains, in which full nonl~nearity is retained but in which the scale of the nonuniformity introduces a small parameter. The first order results agree with the results that Whitham obtained by averaging methods. The perturbation method provides a detailed description and deeper understanding, as well as a consistent development to higher approximations. This method for treating partial differ ential equations is analogous to the "multiple time scale" meth ods for ordinary differential equations in nonlinear vibration theory. It may also be regarded as a generalization of geomet r i cal optics to nonlinear problems. -
Interactions and Resonances
A Macroscopic Plasma Lagrangian and its Application to Wave Interactions and Resonances by Yueng-Kay Martin Peng June 1974 SUIPR Report No. 575 National Aeronautics and Space Administration Grant NGL 05-020-176 National Science Foundation Grant GK-32788X (NASA-CR-138649) A MACROSCOPIC PLASMA N74-27231 LAGRANGIAN AND ITS APPLICATION TO WAVE INTERACTIOUS AND RESONANCES (Stanford Univ.) 262 p HC $16.25 CSCL 201 Unclas G3/25 41289 INSTITUTE FOR PLASMA RESEARCH STANFORD UNIVERSITY, STANFORD, CALIFORNIA NIZ~a A MACROSCOPIC PLASMA LAGRANGIAN AND ITS APPLICATION TO WAVE INTERACTIONS AND RESONANCES by Yueng-Kay Martin Peng National Aeronautics and Space Administration Grant NGL 05-020-176 National Science Foundation Grant GK-32788X SUIPR Report No. 575 June 1974 Institute for Plasma Research Stanford University Stanford, California I A MACROSCOPIC PLASMA LAGRANGIAN AND ITS APPLICATION TO WAVE INTERACTIONS AND RESONANCES by Yueng-Kay Martin Peng Institute for Plasma Research Stanford University Stanford, California 94305 ABSTRACT This thesis is concerned with derivation of a macroscopic plasma Lagrangian, and its application to the description of nonlinear three- wave interaction in a homogeneous plasma and linear resonance oscilla- tions in a inhomogeneous plasma. One approach to obtain -the--Lagrangian is via the inverse problem of the calculus of variations for arbitrary first and second order quasilinear partial differential systems. Necessary and sufficient conditions for the given equations to be Euler-Lagrange equations of a Lagrangian are obtained. These conditions are then used to determine the transformations that convert some classes of non-Euler-Lagrange equations to Euler-Lagrange equation form. The Lagrangians for a linear resistive transmission line and a linear warm collisional plasma are derived as examples. -
Chapter 2. Electrostatics
Chapter 2. Electrostatics Introduction to Electrodynamics, 3rd or 4rd Edition, David J. Griffiths 2.3 Electric Potential 2.3.1 Introduction to Potential We're going to reduce a vector problem (finding E from E 0 ) down to a much simpler scalar problem. E 0 the line integral of E from point a to point b is the same for all paths (independent of path) Because the line integral of E is independent of path, we can define a function called the Electric Potential: : O is some standard reference point The potential difference between two points a and b is The fundamental theorem for gradients states that The electric field is the gradient of scalar potential 2.3.2 Comments on Potential (i) The name. “Potential" and “Potential Energy" are completely different terms and should, by all rights, have different names. There is a connection between "potential" and "potential energy“: Ex: (ii) Advantage of the potential formulation. “If you know V, you can easily get E” by just taking the gradient: This is quite extraordinary: One can get a vector quantity E (three components) from a scalar V (one component)! How can one function possibly contain all the information that three independent functions carry? The answer is that the three components of E are not really independent. E 0 Therefore, E is a very special kind of vector: whose curl is always zero Comments on Potential (iii) The reference point O. The choice of reference point 0 was arbitrary “ambiguity in definition” Changing reference points amounts to adding a constant K to the potential: Adding a constant to V will not affect the potential difference: since the added constants cancel out. -
Canonical Coordinates on Lie Groups and the Baker Campbell Hausdorff Formula
Utah State University DigitalCommons@USU All Graduate Theses and Dissertations Graduate Studies 8-2018 Canonical Coordinates on Lie Groups and the Baker Campbell Hausdorff Formula Nicholas Graner Utah State University Follow this and additional works at: https://digitalcommons.usu.edu/etd Part of the Mathematics Commons Recommended Citation Graner, Nicholas, "Canonical Coordinates on Lie Groups and the Baker Campbell Hausdorff Formula" (2018). All Graduate Theses and Dissertations. 7232. https://digitalcommons.usu.edu/etd/7232 This Thesis is brought to you for free and open access by the Graduate Studies at DigitalCommons@USU. It has been accepted for inclusion in All Graduate Theses and Dissertations by an authorized administrator of DigitalCommons@USU. For more information, please contact [email protected]. CANONICAL COORDINATES ON LIE GROUPS AND THE BAKER CAMPBELL HAUSDORFF FORMULA by Nicholas Graner A thesis submitted in partial fulfillment of the requirements for the degree of MASTERS OF SCIENCE in Mathematics Approved: Mark Fels, Ph.D. Charles Torre, Ph.D. Major Professor Committee Member Ian Anderson, Ph.D. Mark R. McLellan, Ph.D. Committee Member Vice President for Research and Dean of the School for Graduate Studies UTAH STATE UNIVERSITY Logan,Utah 2018 ii Copyright © Nicholas Graner 2018 All Rights Reserved iii ABSTRACT Canonical Coordinates on Lie Groups and the Baker Campbell Hausdorff Formula by Nicholas Graner, Master of Science Utah State University, 2018 Major Professor: Mark Fels Department: Mathematics and Statistics Lie's third theorem states that for any finite dimensional Lie algebra g over the real numbers, there is a simply connected Lie group G which has g as its Lie algebra. -
Hamiltonian Dynamics Lecture 1
Hamiltonian Dynamics Lecture 1 David Kelliher RAL November 12, 2019 David Kelliher (RAL) Hamiltonian Dynamics November 12, 2019 1 / 59 Bibliography The Variational Principles of Mechanics - Lanczos Classical Mechanics - Goldstein, Poole and Safko A Student's Guide to Lagrangians and Hamiltonians - Hamill Classical Mechanics, The Theoretical Minimum - Susskind and Hrabovsky Theory and Design of Charged Particle Beams - Reiser Accelerator Physics - Lee Particle Accelerator Physics II - Wiedemann Mathematical Methods in the Physical Sciences - Boas Beam Dynamics in High Energy Particle Accelerators - Wolski David Kelliher (RAL) Hamiltonian Dynamics November 12, 2019 2 / 59 Content Lecture 1 Comparison of Newtonian, Lagrangian and Hamiltonian approaches. Hamilton's equations, symplecticity, integrability, chaos. Canonical transformations, the Hamilton-Jacobi equation, Poisson brackets. Lecture 2 The \accelerator" Hamiltonian. Dynamic maps, symplectic integrators. Integrable Hamiltonian. David Kelliher (RAL) Hamiltonian Dynamics November 12, 2019 3 / 59 Configuration space The state of the system at a time q 3 t can be given by the value of the t2 n generalised coordinates qi . This can be represented by a point in an n dimensional space which is called “configuration space" (the system t1 is said to have n degrees of free- q2 dom). The motion of the system as a whole is then characterised by the line this system point maps out in q1 configuration space. David Kelliher (RAL) Hamiltonian Dynamics November 12, 2019 4 / 59 Newtonian Mechanics The equation of motion of a particle of mass m subject to a force F is d (mr_) = F(r; r_; t) (1) dt In Newtonian mechanics, the dynamics of the system are defined by the force F, which in general is a function of position r, velocity r_ and time t.