472 research outputs found
A New Superconformal Mechanics
In this paper we propose a new supersymmetric extension of conformal
mechanics. The Grassmannian variables that we introduce are the basis of the
forms and of the vector-fields built over the symplectic space of the original
system. Our supersymmetric Hamiltonian itself turns out to have a clear
geometrical meaning being the Lie-derivative of the Hamiltonian flow of
conformal mechanics. Using superfields we derive a constraint which gives the
exact solution of the supersymmetric system in a way analogous to the
constraint in configuration space which solved the original non-supersymmetric
model. Besides the supersymmetric extension of the original Hamiltonian, we
also provide the extension of the other conformal generators present in the
original system. These extensions have also a supersymmetric character being
the square of some Grassmannian charge. We build the whole superalgebra of
these charges and analyze their closure. The representation of the even part of
this superalgebra on the odd part turns out to be integer and not spinorial in
character.Comment: Superfield re-define
The Negative Dimensional Oscillator at Finite Temperature
We study the thermal behavior of the negative dimensional harmonic oscillator
of Dunne and Halliday that at zero temperature, due to a hidden BRST symmetry
of the classical harmonic oscillator, is shown to be equivalent to the
Grassmann oscillator of Finkelstein and Villasante. At finite temperature we
verify that although being described by Grassmann numbers the thermal behavior
of the negative dimensional oscillator is quite different from a Fermi system.Comment: 8 pages, IF/UFRJ/93/0
Universal Hidden Supersymmetry in Classical Mechanics and its Local Extension
We review here a path-integral approach to classical mechanics and explore
the geometrical meaning of this construction. In particular we bring to light a
universal hidden BRS invariance and its geometrical relevance for the Cartan
calculus on symplectic manifolds. Together with this BRS invariance we also
show the presence of a universal hidden genuine non-relativistic supersymmetry.
In an attempt to understand its geometry we make this susy local following the
analogous construction done for the supersymmetric quantum mechanics of Witten.Comment: 6 pages, latex, Volkov Memorial Proceeding
On Koopman-von Neumann Waves II
In this paper we continue the study, started in [1], of the operatorial
formulation of classical mechanics given by Koopman and von Neumann (KvN) in
the Thirties. In particular we show that the introduction of the KvN Hilbert
space of complex and square integrable "wave functions" requires an enlargement
of the set of the observables of ordinary classical mechanics. The possible
role and the meaning of these extra observables is briefly indicated in this
work. We also analyze the similarities and differences between non selective
measurements and two-slit experiments in classical and quantum mechanics.Comment: 18+1 pages, 1 figure, misprints fixe
Chiral Anomalies via Classical and Quantum Functional Methods
In the quantum path integral formulation of a field theory model an anomaly
arises when the functional measure is not invariant under a symmetry
transformation of the Lagrangian. In this paper, generalizing previous work
done on the point particle, we show that even at the classical level we can
give a path integral formulation for any field theory model. Since classical
mechanics cannot be affected by anomalies, the measure of the classical path
integral of a field theory must be invariant under the symmetry. The classical
path integral measure contains the fields of the quantum one plus some extra
auxiliary ones. So, at the classical level, there must be a sort of
"cancellation" of the quantum anomaly between the original fields and the
auxiliary ones. In this paper we prove in detail how this occurs for the chiral
anomaly.Comment: 26 pages, Latex, misprint fixed, a dedication include
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