N=2 Chern-Simons-Matter Theories Without Vortices

We study ${\cal N}=2$ Chern-Simons-matter theories with gauge group $U_{k_1}(1)\times U_{k_2}(1)$. We find that, when $k_1+k_2=0$, the partition function computed by localization dramatically simplifies and collapses to a single term. We show that the same condition prevents the theory from having supersymmetric vortex configurations. The theories include mass-deformed ABJM theory with $U(1)_{k}\times U_{-k}(1)$ gauge group as a particular case. Similar features are shared by a class of CS-matter theories with gauge group $U_{k_1}(1)\times \cdots \times U_{k_N}(1)$.Comment: 17 page

Rate-Control or Rhythm-Contol: Where do we stand?

Atrial fibrillation is the most common sustained rhythm disturbance and its prevalence is increasing worldwide due to the progressive aging of the population. Current guidelines clearly depict the gold standard management of acute symptomatic atrial fibrillation but the best-long term approach for first or recurrent atrial fibrillation is still debated with regard to quality of life, risk of new hospitalizations, and possible disabling complications, such as thromboembolic stroke, major bleeds and death. Some authors propose that regaining sinus rhythm in all cases, thus re-establishing a physiologic cardiac function not requiring a prolonged antithrombotic therapy, avoids the threat of intracranial or extracranial haemorrhages due to Vitamin K antagonists or aspirin. On the contrary, advocates of a rate control approach with an accurate antithrombotic prophylaxis propose that such a strategy may avoid the risk of cardiovascular and non cardiovascular side effects related to antiarrhythmic drugs. This review aims to explore the state of our knowledge in order to summarize evidences and issues that need to be furthermore clarified

Structural properties and quasiparticule energies of cubic SrO, MgO and SrTiO3

The structural properties and the band structures of the charge-transfer insulating oxides SrO, MgO and SrTiO3 are computed both within density functional theory in the local density approximation (LDA) and in the Hedin's GW scheme for self-energy corrections, by using a model dielectric function, which approximately includes local field and dynamical effects. The deep valence states are shifted by the GW method to higher binding energies, in very good agreement with photoemission spectra. Since in all of these oxides the direct gaps at high-symmetry points of the Brillouin zone may be very sensitive to the actual value of the lattice parameter a, already at the LDA level, self-energy corrections are computed both at the theoretical and the experimental a. For MgO and SrO, the values of the transition energies between the valence and the conduction bands are improved by GW corrections, while for SrTiO3 they are overestimated. The results are discussed in relation to the importance of local field effects and to the nature of the electronic states in these insulating oxides.Comment: 3 figures, accepted in J. Phys.: Condens. Matte

“Narrating” bodies : physical “reflexive” activities between gender images and socio-pedagogical processes : research on the yoga’s representations

This article intends to offer a reflection on how reflexive physical activities can support a socio-pedagogical approach to educating about gender diversity through media communication. We use the term “reflexive” to refer to all those activities aimed at enhancing the person and his relationships, self-realization, selfknowledge, and self-improvement: in other terms, a circuit of bodily experiences that determine bodily knowledge as a social construction (as described by Connel, 2005). These activities focus mainly on ethical purposes, rather than on performative ones. An example of such disciplines can be considered the practice of yoga which is a currently growing phenomenon both in Europe and in the United States. Yoga is practiced today in the USA by 35.2 million adults, by over 2.5 million people in Italy, and is garnering scientific interest in its contributions to balanced, healthy growth of children and adults. The World Health Organization, in its global action plan on physical activity 2018-2030: More Active People for a Healthier World, calls it a means to improve health. The diffusion of these disciplines responds to a personal and social search for meaning that weighs especially heavily on highly secularized Western culture. This diffusion also portrays a media phenomenon, whose images and messages validate and reinforce capitalist ethics. From this point of view, the “mediated” representation of sports bodies appears to apply to the world of consumers. The images of women practicing yoga, oriented toward alternative values rather than beauty and sexuality, are above all confirmed by the purchase of goods and services that are not related to outward personal appearance. Using the results of an analysis carried out in 2021 of two main international yoga magazines, we are going to discuss the role of yoga as a “reflexive” physical activity and its pedagogical potential oriented to the body as a “primary place of experience”, not just a consumer item, but also a tool for education about gender diversity

Introduction to the Proceedings of WGTTG2021

We describe the Italy-South Africa Research Program 2018–2020, focusing on the mobility scheme “Algebraic Graph Theory and Complex Networks” which supported a series of scientific initiatives between the University of Cape Town (Cape Town, South Africa) and the University of Naples Federico II (Naples, Italy) during the years 2018–2021. We sketch the relevant steps of the collaboration, focusing on the creation of a network of researchers between Italy and South Africa in the fields of Graph Theory and Combinatorics. In this context it becomes more relevant the role of the “Workshop on Graphs, Topology and Topological Groups 2021” and of the corresponding proceedings

Experimental observation of bias-dependent non-local Andreev reflection

We investigate transport through hybrid structures consisting of two normal metal leads connected via tunnel barriers to one common superconducting electrode. We find clear evidence for the occurrence of non-local Andreev reflection and elastic cotunneling through superconductor when the separation of the tunnel barrier is comparable to the superconducting coherence length. The probability of the two processes is energy dependent, with elastic cotunneling dominating at low energy and non-local Andreev reflection at higher energies. The energy scale of the crossover is found to be the Thouless energy of the superconductor, which indicates the phase coherence of the processes. Our results are relevant for the realization of recently proposed entangler devices.Comment: 4 pages, 4 figures. Accepted for publication in PR

Topological Decompositions of the Pauli Group and their Influence on Dynamical Systems

In the present paper we show that it is possible to obtain the well known Pauli group P = 〈X,Y,Z | X2 = Y2 = Z2 = 1,(YZ)4 = (ZX)4 = (XY)4 = 1〉 of order 16 as an appropriate quotient group of two distinct spaces of orbits of the three dimensional sphere S3. The first of these spaces of orbits is realized via an action of the quaternion group Q8 on S3; the second one via an action of the cyclic group of order four ℤ(4) on S3. We deduce a result of decomposition of P of topological nature and then we find, in connection with the theory of pseudo-fermions, a possible physical interpretation of this decomposition

Soluble models in 2d dilaton gravity

A one-parameter class of simple models of two-dimensional dilaton gravity, which can be exactly solved including back-reaction effects, is investigated at both classical and quantum levels. This family contains the RST model as a special case, and it continuously interpolates between models having a flat (Rindler) geometry and a constant curvature metric with a non-trivial dilaton field. The processes of formation of black hole singularities from collapsing matter and Hawking evaporation are considered in detail. Various physical aspects of these geometries are discussed, including the cosmological interpretation.Comment: 15 pages, harvmac, 3 figure