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Hamiltonian Formalism in the Presence of Higher Derivatives  [PDF]
A. Morozov
Mathematics , 2007, DOI: 10.1007/s11232-008-0128-2
Abstract: A short review of basic formulas from Hamiltonian formalism in classical mechanics in the case when Lagrangian contains N time-derivatives of n coordinate variables. For non-local models N=infinity.
Multimomentum Hamiltonian Formalism in Field Theory. Geometric Supplementary  [PDF]
G. Sardanashvily
Physics , 1994,
Abstract: The well-known geometric approach to field theory is based on description of classical fields as sections of fibred manifolds, e.g. bundles with a structure group in gauge theory. In this approach, Lagrangian and Hamiltonian formalisms including the multiomentum Hamiltonian formalism are phrased in terms of jet manifolds. Then, configuration and phase spaces of fields are finite-dimensional. Though the jet manifolds have been widely used for theory of differential operators, the calculus of variations and differential geometry, this powerful mathematical methods remains almost unknown for physicists. This Supplementary to our previous article (hep-th/9403172) aims to summarize necessary requisites on jet manifolds and general connections.
Thermo-Statistical description of the Hamiltonian non extensive systems: The reparametrization invariance  [PDF]
L. Velazquez,F. Guzman
Physics , 2006,
Abstract: In the present paper we continue our reconsideration about the foundations for a thermostatistical description of the called Hamiltonian nonextensive systems (see in cond-mat/0604290). After reviewing the selfsimilarity concept and the necessary conditions for the ensemble equivalence, we introduce the reparametrization invariance of the microcanonical description as an internal symmetry associated with the dynamical origin of this ensemble. Possibility of developing a geometrical formulation of the thermodynamic formalism based on this symmetry is discussed, with a consequent revision about the classification of phase-transitions based on the concavity of the Boltzmann entropy. The relevance of such conceptions are analyzed by considering the called Antonov isothermal model.
Multimomentum Hamiltonian Formalism  [PDF]
G. Sardanashvily
Physics , 1994,
Abstract: The standard Hamiltonian machinery, being applied to field theory, leads to infinite-dimensional phase spaces. It is not covariant. In this article, we present covariant finite-dimensional multimomentum Hamiltonian formalism for field theory. This is the multisymplectic generalization of the Hamiltonian formalism in mechanics. In field theory, multimomentum canonical variables are field functions and momenta corresponding to derivatives of fields with respect all world coordinates, not only the time. In case of regular Lagrangian densities, the multimomentum Hamiltonian formalism is equivalent to the Lagrangian formalism, otherwise for degenerate Lagrangian densities. In this case, the Euler-Lagrange equations become undetermined and require additional conditions which remain elusive. In the framework of the multimomentum Hamiltonian machinery, one obtaines them automatically as a part of Hamilton equations. The key point consists in the fact that, given a degenerate Lagrangian density, one must consider a family of associated multimomentum Hamiltonian forms in order to exaust solutions of the Euler-Lagrange equations. We spell out degenerate quadratic and affine Lagrangian densities. The most of field models are of these types. As a result, we get the general procedure of describing constraint field systems.
Hamiltonian formalism of fractional systems  [PDF]
Aleksander Stanislavsky
Physics , 2011, DOI: 10.1140/epjb/e2006-00023-3
Abstract: In this paper we consider a generalized classical mechanics with fractional derivatives. The generalization is based on the time-clock randomization of momenta and coordinates taken from the conventional phase space. The fractional equations of motion are derived using the Hamiltonian formalism. The approach is illustrated with a simple-fractional oscillator in a free state and under an external force. Besides the behavior of the coupled fractional oscillators is analyzed. The natural extension of this approach to continuous systems is stated. The interpretation of the mechanics is discussed.
A canonical formalism of f(T)-type gravity in terms of Lie derivatives  [PDF]
Y. Ezawa,H. Iwasaki,Y. Ohkuwa,S. Watanabe,N. Yamada,T. Yano
Physics , 2005, DOI: 10.1088/0264-9381/23/9/028
Abstract: A canonical formalism of f(R)-type gravity is proposed, resolving the problem in the formalism of Buchbinder and Lyakhovich(BL). The new coordinates corresponding to the time derivatives of the metric are taken to be its Lie derivatives which is the same as in BL. The momenta canonically conjugate to them and Hamiltonian density are defined similarly to the formalism of Ostrogradski. It is shown that our method surely resolves the problem of BL.
The Hamiltonian Formalism for the Generalized Rigid Particles  [PDF]
A. Nersessian
Mathematics , 1998,
Abstract: The Hamiltonian formulation for the mechanical systems with reparametrization-invariant Lagrangians, depending on the worldline external curvatures is given, which is based on the use of moving frame. A complete sets of constraints are found for the Lagrangians with quadratic dependence on curvatures, for the lagrangians, proportional to an arbitrary curvature, and for the Lagrangians, linear on the first and second curvatures.
Second variation of the Helfrich-Canham Hamiltonian and reparametrization invariance  [PDF]
Riccardo Capovilla,Jemal Guven
Mathematics , 2004, DOI: 10.1088/0305-4470/37/23/003
Abstract: A covariant approach towards a theory of deformations is developed to examine both the first and second variation of the Helfrich-Canham Hamiltonian -- quadratic in the extrinsic curvature -- which describes fluid vesicles at mesoscopic scales. Deformations are decomposed into tangential and normal components; At first order, tangential deformations may always be identified with a reparametrization; at second order, they differ. The relationship between tangential deformations and reparametrizations, as well as the coupling between tangential and normal deformations, is examined at this order for both the metric and the extrinsic curvature tensors. Expressions for the expansion to second order in deformations of geometrical invariants constructed with these tensors are obtained; in particular, the expansion of the Hamiltonian to this order about an equilibrium is considered. Our approach applies as well to any geometrical model for membranes.
Pedagogical Introduction to Hamiltonian BRST formalism  [PDF]
Naohisa Ogawa
Physics , 1997,
Abstract: Hamiltonian BRST formalism (FV formalism) includes many auxiliary fields without explanation. Its path-integration has a simple form by using BRST charge, but its construction is quite mechanically and hard to understand physical meaning. In this paper we perform the phase space path-integral with requiring BRST invariance for action and measure, and show that the resultant form is equivalent to the Hamiltonian BRST (FV) formalism in gravitational theory. This explains why so many auxiliary fields are necessary to be introduced. We also find the gauge fixing is automatically done by requiring the BRST invariance of the path-integral measure. This is a pedagogical introduction to Hamiltonian BRST formalism.
Hamiltonian formalism of the DNLS equation with nonvanished boundary value  [PDF]
Hao Cai,Nian-Ning Huang
Physics , 2005, DOI: 10.1088/0305-4470/39/18/016
Abstract: Hamiltonian formalism of the DNLS equation with nonvanishing boundary value is developed by the standard procedure.
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