1,992 research outputs found
Abelian 3-form gauge theory: superfield approach
We discuss a D-dimensional Abelian 3-form gauge theory within the framework
of Bonora-Tonin's superfield formalism and derive the off-shell nilpotent and
absolutely anticommuting Becchi-Rouet-Stora-Tyutin (BRST) and anti-BRST
symmetry transformations for this theory. To pay our homage to Victor I.
Ogievetsky (1928-1996), who was one of the inventors of Abelian 2-form
(antisymmetric tensor) gauge field, we go a step further and discuss the above
D-dimensional Abelian 3-form gauge theory within the framework of BRST
formalism and establish that the existence of the (anti-)BRST invariant
Curci-Ferrari (CF) type of restrictions is the hallmark of any arbitrary p-form
gauge theory (discussed within the framework of BRST formalism).Comment: LaTeX file, 8 pages, Talk delivered at BLTP, JINR, Dubna, Moscow
Region, Russi
Free field representation of Toda field theories
We study the following problem: can a classical Toda field theory be
represented by means of free bosonic oscillators through a Drinfeld--Sokolov
construction? We answer affirmatively in the case of a cylindrical space--time
and for real hyperbolic solutions of the Toda field equations. We establish in
fact a one--to--one correspondence between such solutions and the space of free
left and right bosonic oscillators with coincident zero modes. We discuss the
same problem for real singular solutions with non hyperbolic monodromy.Comment: 29 pages, Latex, SISSA-ISAS 210/92/E
Bi-photon propagation control with optimized wavefront by means of Adaptive Optics
We present an efficient method to control the spatial modes of entangled
photons produced through SPDC process. Bi-photon beam propagation is controlled
by a deformable mirror, that shapes a 404nm CW diode laser pump interacting
with a nonlinear BBO type-I crystal. Thanks to adaptive optical system, the
propagation of 808nm SPDC light produced is optimized over a distance of 2m.
The whole system optimization is carried out by a feedback between deformable
mirror action and entangled photon coincidence counts. We also demonstrated the
improvement of the two-photon coupling into single mode fibers
Aberration cancellation in quantum interferometry
We report the first experimental demonstration of even-order aberration
cancellation in quantum interferometry. The effect is a spatial counterpart of
the spectral group velocity dispersion cancellation, which is associated with
spectral entanglement. It is manifested in temporal interferometry by virtue of
the multi-parameter spatial-spectral entanglement. Spatially-entangled photons,
generated by spontaneous parametric down conversion, were subjected to spatial
aberrations introduced by a deformable mirror that modulates the wavefront. We
show that only odd-order spatial aberrations affect the quality of quantum
interference
ANALYSIS OF THE FACTORS AFFECTING 3D MODELS RESOLUTION – APPLICATION TO THE RECORDING OF VAULTS IN SANGALLO'S HOUSE
The paper will present the extraction of information from a laser scanning survey aimed to support historical studies on the Sangallo's house in Florence. In order to verify some study's hypothesis related to the building history and constructive techniques, high resolution models were needed. The meaning of "resolution" applied to 3D scanning will be briefly discussed stressing the difference between resolution and accuracy. Starting from the analysis of technical specifications of the used instruments, the expected performance of the model is described. The results obtained from acquired data are shown and the paper will conclude proposing some answers to the historian's questions
Integrated and multiscale spatial data to base a gis for the ancient city of hierapolis in Phrygia
Analyticity Properties of Graham-Witten Anomalies
Analytic properties of Graham-Witten anomalies are considered. Weyl anomalies
according to their analytic properties are of type A (coming from
-singularities in correlators of several energy-momentum tensors) or of
type B (originating in counterterms which depend logarithmically on a mass
scale). It is argued that all Graham-Witten anomalies can be divided into 2
groups: internal and external, and that all external anomalies are of type B,
whereas among internal anomalies there is one term of type A and all the rest
are of type B. This argument is checked explicitly for the case of a free
scalar field in a 6-dimensional space with a 2-dimensional submanifold.Comment: 2 typos correcte
Notoph Gauge Theory: Superfield Formalism
We derive absolutely anticommuting Becchi-Rouet-Stora-Tyutin (BRST) and
anti-BRST symmetry transformations for the 4D free Abelian 2-form gauge theory
by exploiting the superfield approach to BRST formalism. The antisymmetric
tensor gauge field of the above theory was christened as the "notoph" (i.e. the
opposite of "photon") gauge field by Ogievetsky and Palubarinov way back in
1966-67. We briefly outline the problems involved in obtaining the absolute
anticommutativity of the (anti-) BRST transformations and their resolution
within the framework of geometrical superfield approach to BRST formalism. One
of the highlights of our results is the emergence of a Curci-Ferrari type of
restriction in the context of 4D Abelian 2-form (notoph) gauge theory which
renders the nilpotent (anti-) BRST symmetries of the theory to be absolutely
anticommutative in nature.Comment: LaTeX file, 12 pages, Talk delivered at SQS'09 (BLTP, JINR, Dubna
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