Classical and Celestial Mechanics

I.I.Kosenko, V.N.Tkhai

e-mai:  kosenko@ccas.ru

There are not a lot of conferences and Symposiums one can find in Russian scientific society like one on Classical and Celestial Mechanics held in Velikie Luki. According to tradition it has been performed last summer from 15 to 20 August 2001. At the beginning Symposium arose as a result of joint efforts of investigators from Moscow and Saint-Petersburg. In general latter ones were the representatives of Saint-Petersburg schools in field of celestial mechanics.

Simposium venue was selected in a natural way: it located in approximately equal distances from two cities cited above. Velikie Luki is peaceful and comfortable town in North West of Russia, South of Pskov region. Registration and sessions were performed in camp “Sunny” relocated in pine forest on the beach of picturesque glacial lake Balasdygn. Conditions created are promoted effective work and rest. All resources need to perform the Symposium were provided by Joint-Stock Holding Company ELVO, President B.N.Karakaev, and ZETO Limited Company, Director General N.N.Koslovsky. Symposium sponsors have organized the rest of participants in natural environment and unforgettable trips to Pushkin Hills and museums of Sofia Kovalevskaya and Ivan Vinogradov.

Symposium organizers are: Russian Academy of Sciences, Branch of Machine-Building, Mechanics, and Control Processes, Computing Center of RAS, Academy of Cosmonautics, Moscow State University, Moscow State Aviation Institute, Moscow State Academy of Instrument Making and Computer Science, International Informatization Academy. Symposium chairman is V.V.Rumyantsev, Academician of RAS. Co-chairmen are: P.S.Krasil’nikov, V. N. Tkhai. Scientific secretary is I.I.Kosenko. In Symposium work take a part participants from Algeria, Brazil, Georgia, Italy, Russia, Ukraine, France.

Symposium was performed with financial support of Russia Fund for Basic Researches, grant 01-0110101. Also special financial support was provided for young participants.

Symposium was dedicated to 80th birthday of Academician V.V.Rumyantsev.

Scientific program was including: plenary sessions (A), mini-Symposium on joint sessions of two sections (B), mini-Symposium in frame of classical mechanics section (C), mini-Symposium in frame of celestial mechanics section (D), and computer presentation of PMM journal electronic version Web site. Time-limit was as follow: in category A were 40 minutes per lecture, in category B were 30 minutes per lecture, in categories C and D were 30 minutes per message. Then let us give more detailed structure of cited sessions categories.

In class B were included the following mini-Symposium: Methods of Classical and Celestial Mechanics – B1, and Selected Problems of Classical and Celestial Mechanics – B2. In class C were included the mini-Symposium: Analytical Mechanics – C1, Theory of Stability and Bifurcations – C2, Regular and Chaotic Dynamics – C3, Oscillations of Mechanical Systems – C4, Dynamics of Rigid and/or Deformable Bodies – C5. Correspondingly in class D were included the mini-Symposium: The Problems of Three and N Bodies – D1, Periodic and Almost Periodic Orbits, Resonances – D2, Investigations on Dynamics of Solar System Planets – D3, Dynamics of Rotational Motion of Celestial Bodies – D4, Dynamics of Orbital Systems – D5.

Two lectures have performed by the order of Scientific Committee namely: A.V.Karapetyan (Moscow), S.Ya.Stepanov (Moscow), R.S.Sulikashwili (Tbilisi), “The 80-th Anniversary of Academician V.V.Rumyantsev”; Yu.P.Gupalo (Moscow), “The Journal Prikladnaya Matematika i Mekhanika as a Booster for Advances in Mechanics”.

Below we will give short abstracts of lectures from A and B categories.

A.S.Andreev (Ulyanovsk). “Stability with Respect to Part of the Variables: Some Results and Perspectives of Their Development”. The observation of the results concerning investigation of the stability with respect to part of the variables on the base of Lyapunov functions method and of limit equations one from the viewpoint of perspective of their usage and development is introduced.

A.S.Andreev (Ulyanovsk), E.B.Kim (Ulyanovsk), C.Risito (Parma). “On the Stability of Generalized Stationary and Quasistationary Motions”. In the work sufficient conditions of unconditional stability of generalized steady and quasi steady motions are obtained. Some examples are considered.

V.V.Beletsky (Moscow), M.L.Pivovarov (Moscow), A.A.Savchenko (Moscow). “Regular and Chaotic Attitude Motion of Dumb-Bell-Spacecraft”. Attitude motion of orbiting tether connected two-body system is considered. The model of dumb-bell-spacecraft in elliptic orbit is used. Regular and chaotic motions of the system with tense tether are studied.

S.V.Bolotin (Moscow). “Chaotic Trajectories of the Second Species for the Restricted 3-Body Problem”. For the n-center problem of one particle moving in the potential of attracting centers of small mass fixed in an arbitrary smooth potential and magnetic field. Large subshifts of solutions of this type for the circular restricted 3-body problem of celestial mechanics are obtained.

A.D.Bruno (Moscow). “Families of Periodic Solutions to the Beletsky Equation”. The survey of results of two parametric families of periodic solutions constructing is given. The structure of families of symmetric and asymmetric solutions is considered. Data on resonant rotations of bodies in Solar System are compared with computed families of periodic solutions to the Beletsky equation.

B.M.Darinskii (Voronezh), Yu.I.Sapronov (Voronezh). “Bifurcations of Extremals, Phase Transitions, and Characteristic CW-complexes”. Investigation of extremals of smooth functional in smooth Banach manifold often can be reduced to similar problem of analysis of extremals of key function (in a finite-dimensional manifold of key parameters). For spread in theory of crystals singularity of n-dimensional pleat type (defined by a quartic part of Taylor decomposition of key function) the rather complete lists of bif-decompositions had been received at n £ 3.

G.Cantarelli (Cagliari). “Stability of the Origin of Scleronomic Systems, I”. A holonomic scleronomic mechanical systems with bilateral and frictionless time independent constraints are considered.

A.V.Karapetyan (Moscow). “Steady Motions of Mechanical Systems”. Problems of the existence and stability of steady motions of mechanical systems with first integrals are discussed. Recently, such the theory was modified for the existence and stability problems of steady motions of dynamical systems with a non-increasing energy function and first integrals (in particular, for conservative and dissipative mechanical systems with symmetry).

V.V.Kozlov (Moscow). “General Vortex Theory, Changeable System Dynamics and the Lie Groups”. Problems, connected with the motion of changeable mechanical systems are discussed. It mean that the internal forces change mass geometry of the system. Equations of motion are reduced to the non-autonomous first order system of ordinary differential equations on the Lie group. The hydrodynamic analogy for the phase flow of system derived is used. General results are applied to the "falling cat" problem and the problem of the motion of the body with rigid surface in the liquid.

I.I.Kosenko (Moscow). “Methods to Describe Impacts in Dynamics of Tethered Satellite Systems”. The toolkit of computational procedures to construct various models of tethered satellite system dynamics is built. Two approaches are under consideration. The first one is the simulation of successive impacts in unrestricted form when orbits are not necessary to be Keplerian. The second approach is to use the method of reflection in dynamics with impacts.

P.S.Krasil'nikov (Moscow). “The Generalized Classical Method of the Construction of V-Functions from the First Integrals”. The new heuristic method generalizing the classical construction of V-function from first integrals is described. It is shown the most of the investigated stability problems from classical mechanics are covered and ordered by new method. By this method, some algebraic unsolvable stability problems of ordinary differential equations are investigated.

A.L.Kunitsyn (Moscow). “On the Libration Points of the Photogravitational 3-Body Problem”. The positions of relative equilibrium and their stability in the restricted photogravitational 3-body problem when a passively gravitating particle is not only attracted by the main bodies but is subjected also to the light pressure from each of the primeries is considered. The review of the results on the determination, clasification and stability investigations of the possible libration points both in the circular and the elliptic case obtained by different authors are presented. Conditions of stability obtained previously are analyzed with the new point of view permitting to get more natural visual representation.

A.P. Markeev (Moscow). “Nonlocal Problem of Stability of Periodic Motions of Hamiltonian Systems”. Periodic motion, which is orbital unstable because of the presence in the system of a resonance of the second or third order is assumed to be exist. Despite of the instability, the trajectories of the disturbed motion can remain in the limited vicinity of trajectories of the undisturbed periodic motion for all moments of time. Some interesting applications for description of instabilities in asteroid belt are considered.

V.M.Matrosov (Moscow), I.A.Finogenko (Irkutsk). “Analytical Dynamics of Multibody Systems with Dry Friction”. Analytical dynamics, developed by the authors, of Multibody Systems with dry friction in kinematic pairs of one degree of freedom is presented. The results clarify known paradoxes and derive the general theory of mechanical systems with friction motion.

V.V.Rumyantsev (Moscow). “Routh's Equations and Variational Principles”. Holonomic mechanical systems in Routh's variables with equations of motion both of Lagrangian and Hamiltonian type are considered. The variational principles of d'Alembert-Lagrange, Hamilton-Ostrogradsky, Hamilton (in the third form), as well as Hölder's principle and one of the minimal action in Lagrange and Hamilton forms are given in Routh's variables.

A.S.Sumbatov (Moscow). “On the Quasi-Static Model of Motion of a Particle along the Plane with Dry Friction”. 3-dimensional motion of a particle subjected to elastic and damped forces is considered. The particle moves along a plane and can leave it. The force of dry (Coulomb) friction acts on the particle from this plane. Within the framework of the quasi-static statement of the problem the conditions of the existence and uniqueness of motions coherent with the Coulomb friction law are examined. Unlike another considerations of this problem the most general case of permanent positive matrix of the coefficients of elasticity is treated.

V.N.Tkhai (Moscow). “Reversible Dynamical Models in Celestial Mechanics”. The reversible problems of celestial mechanics are investigated. Three-body problem, satellite in the plane of the elliptic orbit and tethered satellite system are analyzed in details.

D.P.Chevallier (Paris). “Objectivity and Dynamics of Generalized Rigid Bo­dy”. Importance of the objectivity (or frame-indifference) principle in mechanics of continua was pointed out by W. Noll. However, its application to dynamics is still questioned in relation with objectivity of inertial forces and torques. It is proved that most of the features of dynamics of ordinary or generalized rigid body are actually mathematical consequences of the principle of objectivity of inertial forces (within a suitable meaning) and of geometry (displacement group).

Totally numbers of messages distributed over mini-Symposium were as follow: C1 – 6, C2 – 11, C3 – 8, C4 – 5, C5 – 14, D1 – 3, D2 – 6, D3 – 4, D4 – 3, D5 – 5. Work in sessions performed in harmony by all participants. Lectures and messages followed by discussions sometimes with excitement.