Coupling Nonlinear Sigma-Matter to Yang-Mills Fields: Symmetry Breaking Patterns

We extend the traditional formulation of Gauge Field Theory by incorporating the (non-Abelian) gauge group parameters (traditionally simple spectators) as new dynamical (nonlinear-sigma-model-type) fields. These new fields interact with the usual Yang-Mills fields through a generalized minimal coupling prescription, which resembles the so-called Stueckelberg transformation, but for the non-Abelian case. Here we study the case of internal gauge symmetry groups, in particular, unitary groups U(N). We show how to couple standard Yang-Mills Theory to Nonlinear-Sigma Models on cosets of U(N): complex projective, Grassman and flag manifolds. These different couplings lead to distinct (chiral) symmetry breaking patterns and \emph{Higgs-less} mass-generating mechanisms for Yang-Mills fields.Comment: 11 pages. To appear in Journal of Nonlinear Mathematical Physic

Conformal Spinning Quantum Particles in Complex Minkowski Space as Constrained Nonlinear Sigma Models in U(2,2) and Born's Reciprocity

We revise the use of 8-dimensional conformal, complex (Cartan) domains as a base for the construction of conformally invariant quantum (field) theory, either as phase or configuration spaces. We follow a gauge-invariant Lagrangian approach (of nonlinear sigma-model type) and use a generalized Dirac method for the quantization of constrained systems, which resembles in some aspects the standard approach to quantizing coadjoint orbits of a group G. Physical wave functions, Haar measures, orthonormal basis and reproducing (Bergman) kernels are explicitly calculated in and holomorphic picture in these Cartan domains for both scalar and spinning quantum particles. Similarities and differences with other results in the literature are also discussed and an extension of Schwinger's Master Theorem is commented in connection with closure relations. An adaptation of the Born's Reciprocity Principle (BRP) to the conformal relativity, the replacement of space-time by the 8-dimensional conformal domain at short distances and the existence of a maximal acceleration are also put forward.Comment: 33 pages, no figures, LaTe

Describing two-mode squeezed-light experiments without two-mode entanglement or squeezing

In a recent work [Phys. Rev. A $\mathbf{102}$, 053723 (2020)] we have shown that experiments that produce and characterize single-mode light squeezing can be explained in a way where no single-mode squeezed light state is produced in the setup. Here we apply the same ideas to demonstrate that experiments that produce and characterize two-mode light squeezing can also be explained without the production of two-mode squeezed light states. In particular, we show that there is no entanglement between the signal and idler "twin beam" modes. This fact may be surprising, since this setup is frequently used to implement entangled-based quantum information protocols such as quantum teleportation. Our work brings an alternative view of the phenomenon. We generalize the Luis and S\'anchez-Soto's two-mode relative phase distribution [Phys. Rev. A $\mathbf{53}$, 495 (1996)] to treat four modes, showing that a general physical explanation for the noise reduction in the experiments is a better definition of a phase relation among the four involved optical modes: Signal, idler, and two local oscillators.Comment: 7 pages, 3 figure

Group Approach to Quantization of Yang-Mills Theories: A Cohomological Origin of Mass

New clues for the best understanding of the nature of the symmetry-breaking mechanism are revealed in this paper. A revision of the standard gauge transformation properties of Yang-Mills fields, according to a group approach to quantization scheme, enables the gauge group coordinates to acquire dynamical content outside the null mass shell. The corresponding extra (internal) field degrees of freedom are transferred to the vector potentials to conform massive vector bosons.Comment: 21 pages, LaTeX, no figures; final for

MODELOS TÁTEIS SOBRE O SISTEMA REPRODUTOR FEMININO: UM ESTUDO EXPLORATÓRIO COM UMA ESTUDANTE CEGA

A investigação acerca da deficiência visual, apesar de sua complexidade, vem se consolidando nos últimos anos no Brasil. Nesta perspectiva, o objetivo da pesquisa baseou-se em descrever a utilização de modelos táteis sobre o Sistema Reprodutor Feminino, da disciplina de Ciências, a partir de um estudo exploratório realizado com uma estudante cega. O sujeito de 15 anos de idade, cursava a 8ª série do Ensino Fundamental em uma escola da rede municipal de ensino público no município de Linhares/ES e frequentava a sala de recursos no contraturno. Esta estudante apresentava dificuldades quanto ao conhecimento do corpo e suas transformações, para tanto, foi estruturado e aplicado um Módulo Educacional, cuja abordagem perpassou a base teórica que circunda o tema em questão na busca por promover maior esclarecimento e autonomia à estudante cega incluindo modelos táteis. Os temas abordados foram Puberdade, Ciclo Menstrual, Sistema Reprodutor Feminino, Gravidez, Doenças Sexualmente Transmissíveis DST, Mitos e Tabus e Sexo e Sexualidade. Os modelos táteis utilizados foram: um sobre o Sistema Reprodutor e outro sobre a Tabelinha do Ciclo Menstrual. A abordagem metodológica deste estudo teve o enfoque qualitativo exploratório de caráter descritivo. Teve como sujeitos a estudante cega, a professora do atendimento educacional especializado, o monitor e duas pedagogas da escola onde funcionava a sala de recursos. Os instrumentos de coleta de dados consistiram em observações espontâneas no contexto do ensino regular registradas em diário de campo e entrevistas semiestruturadas no contexto escolar e familiar. Foram utilizados recursos de áudio-gravação, vídeo-gravação e, em alguns momentos, registros fotográficos. A análise dos dados evidenciou que a estudante cega não diferenciava sua aprendizagem dos estudantes videntes, o que vai diferenciar são os mecanismos utilizados para que ela tenha acesso ao currículo e se aproprie do conhecimento quando este for ministrado. Por meio da análise, também foi possível identificar que a escola comum apresentava um currículo empobrecido diante das necessidades da estudante com deficiência. Pode-se concluir que as dificuldades apresentadas pela estudante cega são mais de ordem social do que biológica, pois a família não dava continuidade às ações desenvolvidas pela sala de recursos, retardando o processo de autonomia do sujeito cego, colocando-a em desvantagem perante a sociedade. No que tange, a escola comum, na qual a estudante cega estudava, conclui-se que não é integrativa e nem inclusiva, ela está nesse entre meio, porém, é complexa e paradoxal, mas também não é excludente

Dark Tourism in the land of Sunshine: An intercultural business model for the routes of death and disaster in Portugal

The main goal of this dissertation is the creation and subsequent implementation of dark tourism routes in Portugal, following a business model that already exists in other cultures. This typology of tourism is an extension of cultural tourism and is classified by the search for places where once disasters, suffering and death occurred. Thus, concentration camps, inactive prisons, serial killers' homes, cemeteries, and all other places that fit into the patterns of death, tragedy and suffering can be considered dark tourism sites. In Portugal, there are some places associated with the practice of dark tourism, although this type of business is not yet sufficiently explored. Therefore, this dissertation intends to use the country’s heritage, which is one of the levers for promoting tourism and an important factor of development, thus justifying the elaboration of a conceptual map associated with tourism. With the delineation of routes in this dissertation, we intend not only to introduce this market niche in the country, but also to contribute innovatively to the tourist dynamics, in order to blur the existing seasonality, which arises from the demand for sun and sea tourism. With the conception and design of these routes, we intend to make a pioneering contribution to the creation of a platform to promote dark tourism in the country. The creation of a business model and a marketing plan results from the need to assess the viability of the implementation of this project, and to discuss the best strategies for implementing it

Almidón resistente: una fracción indigestible en los alimentos

Resistant starch (RS), the dietary starch that scape digestion in the small intestine, can yields up to 20% of the starch in cereal and legume products. Several fractions contribute to the total RS of foods: retrograded amylose, starch inaccessible to digestive enzymes because of mechanical barriers, chemically modified starch fragments, undigested starch due to α-amylase inhibitors and starch complexed with other food components. RS is formed in products processed following heat treatments (baking, extrusion, autoclaving, etc.). RS produces significant fecal bulking and is partially fermentable by anaerobic bacteria of the colon. On the other hand, the relation of resistant starch with the glucose and insulin response in human subjects is an important nutritional effect. RS analytical methods are reported.El almidón resistente (RS), fracción de almidón de la dieta que no es digerido en el intestino delgado, puede alcanzar hasta un 20% del almidón en productos derivados de cereales y legumbres. Varias fracciones contribuyen al contenido total de almidón resistente: amilosa retrogradada, almidón inaccesible físicamente a los enzimas digestivos, almidón indigestible debido a inhibición de α-amilasas y almidón complejado con otros constituyentes de los alimentos. El almidón resistente se forma en productos que han sufrido tratamientos térmicos (panificación, extrusión, autoclave, etc.) El RS aumenta el volumen de heces y es fermentado parcialmente en el colon por bacterias anaeróbicas. Igualmente, está relacionado con los niveles de glucosa en sangre y la respuesta de insulina en humanos. Se describen los métodos analíticos para su determinación