4,060 research outputs found
Geometrical properties of Riemannian superspaces, observables and physical states
Classical and quantum aspects of physical systems that can be described by
Riemannian non degenerate superspaces are analyzed from the topological and
geometrical points of view. For the N=1 case the simplest supermetric
introduced in [Physics Letters B \textbf{661}, (2008),186] have the correct
number of degrees of freedom for the fermion fields and the super-momentum
fulfil the mass shell condition, in sharp contrast with other cases in the
literature where the supermetric is degenerate. This fact leads a deviation of
the 4-impulse (e.g. mass constraint) that can be mechanically interpreted as a
modification of the Newton's law. Quantum aspects of the physical states and
the basic states and the projection relation between them, are completely
described due the introduction of a new Majorana-Weyl representation of the
generators of the underlying group manifold. A new oscillatory fermionic effect
in the part of the vaccum solution involving the chiral and antichiral
components of this Majorana bispinor is explicitly shown.Comment: 16 pags. 3 figures. To Anna Grigorievna Kartavenko and Academic
Professor Alexei Norianovich Sissakian, in memoria
Algebraic structures, physics and geometry from a Unified Field Theoretical framework
Starting from a Unified Field Theory (UFT) proposed previously by the author,
the possible fermionic representations arising from the same spacetime are
considered from the algebraic and geometrical viewpoint. We specifically
demonstrate in this UFT general context that the underlying basis of the single
geometrical structure P (G,M) (the principal fiber bundle over the real
spacetime manifold M with structural group G) reflecting the symmetries of the
different fields carry naturally a biquaternionic structure instead of a
complex one. This fact allows us to analyze algebraically and to interpret
physically in a straighforward way the Majorana and Dirac representations and
the relation of such structures with the spacetime signature and non-hermitian
(CP) dynamic operators. Also, from the underlying structure of the tangent
space, the existence of hidden (super) symmetries and the possibility of
supersymmetric extensions of these UFT models are given showing that
Rothstein's theorem is incomplete for that description. The importance of the
Clifford algebras in the description of all symmetries, mainly the interaction
of gravity with the other fields, is briefly discussed.Comment: To be published in IJTP, last corrected version. This work is devoted
to the memory of the Prof. Academician Vladimir Georgievich Kadyshevsky. 21
pages, no figures. References added and misprints/typos correcte
Coherent states, vacuum structure and infinite component relativistic wave equations
It is commonly claimed in the recent literature that certain solutions to
wave equations of positive energy of Dirac-type with internal variables are
characterized by a non-thermal spectrum. As part of that statement, it was said
that the transformations and symmetries involved in equations of such type
correspond to a particular representation of the Lorentz group. In this paper
we give the general solution to this problem emphasizing the interplay between
the group structure, the corresponding algebra and the physical spectrum. This
analysis is completed with a strong discussion and proving that: i) the
physical states are represented by coherent states; ii) the solutions in
previous references [1] are not general, ii) the symmetries of the considered
physical system in [1] (equations and geometry) do not correspond to the
Lorentz group but to the fourth covering: the Metaplectic group Mp(n).Comment: To be published in the IJGMMP, 12 pages , no figure
Quantum particle on a Mobius strip, coherent states and projection operators
The coherent states for a quantum particle on a M\"{o}bius strip are
constructed and their relation with the natural phase space for fermionic
fields is shown. The explicit comparison of the obtained states with previous
works where the cylinder quantization was used and the spin 1/2 was introduced
by hand is given, and the relation between the geometrical phase space,
constraints and projection operators is analyzed and discussed.Comment: 14 pgs., no figure
Charge dynamics and "in plane" magnetic field I: Rashba-Dresselhauss interaction, Majorana fermions and Aharonov-Casher theorems
The 2-dimensional charge transport with parallel (in plane) magnetic field is
considered from the physical and mathematical point of view. To this end, we
start with the magnetic field parallel to the plane of charge transport, in
sharp contrast to the configuration described by the theorems of Aharonov and
Casher where the magnetic field is perpendicular. We explicitly show that the
specific form of the arising equation enforce the respective field solution to
fulfil the Majorana condition. Consequently, as soon any physical system is
represented by this equation, the rise of fields with Majorana type behaviour
is immediately explained and predicted. In addition, there exists a quantized
particular phase that removes the action of the vector potential producing
interesting effects. Such new effects are able to explain due the geometrical
framework introduced, several phenomenological results recently obtained in the
area of spintronics and quantum electronic devices. The quantum ring as spin
filter is worked out in this framework and also the case of the quantum Hall
effect.Comment: Accepted in International Journal of Geometric Methods in Modern
Physics (IJGMMP) Vol. 12 (2015), no figures. General references added,
english improved. arXiv admin note: text overlap with arXiv:quant-ph/0701076,
arXiv:1302.3641 by other author
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