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Shift of invariants

Fig. 4. Shift of invariant point M with increasing polymer concentration. Fig. 4. Shift of invariant point M with increasing polymer concentration.
Thus, a family of shifts of invariants can be hereafter understood either as a set p or as a set resulting from the solution of the relations (1). After this remark, we may formulate the criterion of completeness of the family of shifts of invariants without imposing any additional limitations on the Lie algebra G. [Pg.199]

Theorem 4.1.10 (Bolsinov). Let G be an arbitrary Bnite-dimensional complex Lie algebra, 5 = y Gr codim 0(y) > indC a set of singular elements from G. Shifts of invariants by the covector of general position form a complete involutive set on G if and only if codim 5 2. [Pg.199]

A family of shifts of invariants forms a complete involutive set of G if and only if for almost all x 6 G a corresponding subspace M is of a dimension equal to (dimG -f indG) however, this definition of completeness is not very convenient in this case and we will therefore use another. For this purpose consider the subspace M = 6 G (x, [, ly)) = OViy E M. The subspace M C G can be conditionally called a skew-orthogonal complement of M at the point x EG. It is clear that M C M. Therefore, if the element x E is regular, then the condition dim M = I (dim G ind G) is equivalent to M = M. The idea of the proof consists in comparison of the two subspaces, M and M. [Pg.200]

Compatible Poisson brackets on Lie algebras were analyzed in the paper by Reyman [117], where such brackets appeared from infinite-dimensional graduated Lie algebras and were applied to the study of the various generalizations of Toda chains. In the same paper [117], Reyman pointed out the Hamiltonian property of the Euler equations for the shifts of invariants of semisimple Lie algebras indicated earlier in the paper [247]. [Pg.218]

The idea of the proof consists in the choice of the point x -h ey so as to make the explicit form of these differentials be much simpler. Then the problem turns out to reduce to the result of Fomenko and Mischenko concerning completeness of the involutive family of shifts of invariants in the case of a semisimple Lie algebra. [Pg.246]

This statement is a reformulation of the theorem of Fomenko and Mischenko on completeness of the family of shifts of invariants in the case of a sembimple complex Lie algebra. See [91]. It can be easily show that the shifts of invariants of a real semisimple Lie algebra also form a complete involutive family of functions. [Pg.246]

This is exactly the autonomous linearized Hamiltonian (7), the dynamics of which was discussed in detail in Section II. One therefore finds the TS dividing surface and the full set of invariant manifolds described earlier one-dimensional stable and unstable manifolds corresponding to the dynamics of the variables A<2i and APt, respectively, and a central manifold of dimension 2N — 2 that itself decomposes into two-dimensional invariant subspaces spanned by APj and AQj. However, all these manifolds are now moving manifolds that are attached to the TS trajectory. Their actual location in phase space at any given time is obtained from their description in terms of relative coordinates by the time-dependent shift of origin, Eq. (42). [Pg.223]

ThenWs(gfe( j) and Wu 7e(t)) intersect transversely at(xh(rio)+0(e),9 j and consequently (from, theS male-Birkhoff homoclinic theorem) for the map P there exists an integer n > 1 that P has an invariant Cantor set on which it is topologically conjugate to a full shift of N symbols. [Pg.116]

The coordinates indicated in the reported partial list of invariant lattice complexes correspond to the so-called standard setting and to related standard representations. Some of the non-standard settings of an invariant lattice complex may be described by a shifting vector, defined in terms of fractional coordinates, in front of the symbol. The most common shifting vectors also have abbreviated symbols P represents 14, A,AP (that is the coordinates which are obtained by adding A, Vi, Ai to those of P, that is coordinates 14, 14, A), J represents A, A, A J (coordinates A, 0, 0 0, A, 0 0, 0, A) F" represents A,A,AF (coordinates At, A, A A, 3A, A 3A, A, 3A 3A, A, A) and F" represents A, /, 3A F. It can be seen, moreover, that the complex D corresponds to the coordinates F + F". [Pg.118]

In conclusion, notice also that in terms of combinations of invariant lattice complexes, the positions of the atoms in the level X can be represented by 2A, A, A G, and those in the level % by A, A, M G (where G is the symbol of the graphitic net complex, here presented in non-standard settings by means of shifting vectors). [Pg.647]

In quantum electrodynamics (QED) the potentials asume a more important role in the formulation, as they are related to a phase shift in the wavefunction. This is still an integral effect over the path of interest. This manifests itself in the phase shift of an electron around a closed path enclosing a magnetic field, even though there are no fields (approximately) on the path itself (static conditions). As can be shown the result of such an experiment is gauge-invariant, allowing the use of various choices of the vector potential (all giving the same result). [Pg.612]

What can be tested As mentioned before, CPT invariance guarantees the equality of masses, charges and lifetimes of particles and antiparticles. This means that the experimental investigations of masses, charges, etc. of particle - antiparticle pairs are tests of CPT symmetry. Such experiments are not easy to do with the charged particles themselves (because of their interactions with stray fields). Comparison of neutral atom - antiatom pairs is much more convenient. In particular, the fine structure, hyperfine structure and Lamb shifts of atoms and antiatoms should be identical - and can be tested in laboratory. [Pg.192]

In order to analyze these data, the frequency shift of geffectivecan be calculated by averaging over all orientations the anisotropic shift derived from a static spin Hamiltonian [67]. This treatment is based on the assumptions that molecular motion neither changes the spin precession rate nor perturbs the states and, thus, that the center of gravity of the spectrum is invariant even in presence of some motional averaging. For the allowed 11/2) <-> <-l/2 transition under perturbation theory, with expressions valid up to the third order, this shift is given by [47] ... [Pg.220]

The 119Sn chemical shift of dimethyltin dichloride in carbon tetrachloride and other non-polar solvents remains practically invariant to large changes in concentration. It has a value of ca. +140 ppm. This indicates the ease with which the molecules are able to dissociate into discrete tetrahedral species in solution as a result of the very weak inter-molecular Sn... Cl bonds which exist in crystalline dimethyltin dichloride. (55) On the other hand, a chemical shift-concentration study of trimethyltin formate in deuterochloroform solution (56) has revealed a dramatic change in chemical shift from +2-5 ppm for a 3 M solution to + 152 ppm on dilution to 0-05 m in the same solvent. This has been attributed to self-association of monomeric tetrahedral trimethyltin formate molecules, [3]. As the concentration is increased, five-coordinate oligomeric or polymeric species, [4], could be formed. These are known to exist in the solid state. (57)... [Pg.303]

At Ms temperature TiNi initiates a uniform (inhomogeneous) distortion of its lattice — through a collective atomic shear movement. The lower the temperature, the greater the magnitude of shear movements. As a result, between Ms and Mr temperature the crystal structure is not definable. In sharp contrast, other known martensitic transformations initiate a nonuniform (heterogeneous) nucleation at Ms and thereafter the growth of martensite is achieved by shifting of a two dimensional plane known as invariant plane [28] at a time. Thus, between Ms and Mr temperature the crystal structure is that of austenite and/or martensite . [Pg.124]


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See also in sourсe #XX -- [ Pg.4 , Pg.190 ]




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