New vector bosons and the diphoton excess

We consider the possibility that the recently observed diphoton excess at $\sim 750$ GeV can be explained by the decay of a scalar particle ($\varphi$) to photons. If the scalar is the remnant of a symmetry-breaking sector of some new gauge symmetry, its coupling to photons can be generated by loops of the charged massive vectors of the broken symmetry. If these new $W^\prime$ vector bosons carry color, they can also generate an effective coupling to gluons. In this case the diphoton excess could be entirely explained in a simplified model containing just $\varphi$ and $W^\prime$. On the other hand if $W^{\prime}$ does not carry color, we show that, provided additional colored particles exist to generate the required $\varphi$ to gluon coupling, the diphoton excess could be explained by the same $W^{\prime}$ commonly invoked to explain the diboson excess at $\sim 2$ TeV. We also explore possible connections between the diphoton and diboson excesses with the anomalous $t\bar{t}$ forward-backward asymmetry.Comment: Latex 8 pages, 1 figure. Extended discussion, new references. Matches published versio

Attitudes toward mental illness among college students in Nuevo Leon, México = Actitudes hacia las enfermedades mentales en estudiantes universitarios de Nuevo León, México

Stigma associated with mental illness has detrimental effects on the treatment and prevention of these diseases. The aim of this study was to analyze attitudes toward mental illness in a sample of university students in Nuevo Leon, Mexico. Results. Nine hundred and forty-three students were surveyed, 66.9% believe that genetic and familial factors are the cause of mental illness. Among 20-30% believe that people with mental illness are a nuisance for people; between 12-14% would be ashamed of having a family member with mental illness and people know it; and 61.8% would be able to maintain a friendship with a person who have mental illness. Conclusions. Over 50% of respondents have favorable attitudes towards patients with mental illness and less than 30% attitudes of social distancing

Kinetic wealth-exchange model of economic growth

En esta tesis se propone un modelo cinético de intercambio de riqueza con crecimiento económico (KWEMEG) en el que se explora el efecto del ahorro de la producción, los im- puestos con beneficio tributario y la aversión al intercambio, sobre las distribuciones de riqueza y de dinero. Este modelo se obtiene a partir de una extensión al formalismo mi- croeconómico del modelo de Chakraborti y Chakrabarti (CCM), donde las preferencias de consumo se describen mediante funciones de utilidad tipo Cobb-Douglas. Al maximizar es- tas funciones, sujetas a ciertas restricciones sobre el consumo, se obtienen reglas generales de interacción entre agentes económicos, caracterizadas por la emergencia de un régimen conservativo, donde la riqueza total se mantiene constante en el tiempo y las interacciones entre agentes se reducen a meros intercambios monetarios; y un régimen no conservativo, en el cual la riqueza crece exponencialmente, induciendo un efecto de crecimiento económi- co a tasa constante. Como casos particulares del KWEMEG se presentan por separado en esta tesis tres nuevos modelos en el contexto de la econofı́sica, que extienden el CCM. Su dinámica macroscópica se estudia analı́ticamente en todos los casos, utilizando la ecuación cinética de Boltzmann; y numéricamente por medio de simulaciones de Monte Carlo. Esto permite ajustar las distribuciones emergentes a densidades de probabilidad tipo gamma, y establecer relaciones analı́ticas para sus parámetros, ası́ como para el ı́ndice de Gini, con el cual se estudia el nivel de desigualdad en las distribuciones. Adicionalemente, en el régimen no conservativo es posible estudiar distribuciones auto-semejantes utilizando una aproxima- ción de campo medio, que abre la puerta a la discusión sobre la posible existencia de colas de Pareto. Como un resultado general, al agregar en el modelo un efecto relacionado con el ingreso por salario, se obtiene como una propiedad emergente la Segunda ley fundamental del capitalismo, de Piketty. Las ideas propuestas en este trabajo atan algunos de los problemas de la economı́a moderna con el discurso tradicional de los modelos cinéticos de intercambio y proponen un puente que conecta de forma efectiva la microfundamentación basada en la maximización de la función de utilidad y los modelos no conservativos. Ambos resultados son novedosos en el contexto de la econofı́sica.This thesis proposes a Kinetic wealth-exchange model of economic growth (KWEMEG) which explores the effects of saving of production, tax benefits with redistribution, and exchange aversion, over the wealth and the money distributions. The model is achieved extending the microeconomic formalism of the Chakraborti and Chakrabarti model (CCM), based on the Cobb-Douglas utility functions describing the preferences for consumption. The maximization of this functions, subjected to certain constraints over consumption leads to general rules of interaction between economic agents that induces the emergence of a conservative regime, where the total wealth of the system remains constant in time, and the interactions between agents are reduced to mere monetary exchanges; and a non-conservative regime, where the wealth and income increase exponentially, inducing an effect of economic growth with a constant rate. The particular cases of the KWEMEG set three new models in the context of econophysics that extend the CCM. All the cases are presented separately in the thesis, and their macroscopic dynamics are studied using the Boltzmann kinetic equation and Monte Carlo simulations, which allows to fit the emergent distributions to the gamma probability density function and to establish analytical relations for its parameters and the evolution of the economic inequality in terms of the Gini index. In addition, it is possible to study a mean field approach for self-similar distributions that allows to discuss the possibility of Pareto tails in the non-conservative regime. As a general result, the model leads to Piketty’s second fundamental law of capitalism as an emergent property, by adding an effect of income due to salary. The ideas developed in this work tie some of the problems of modern economics with the traditional speech of kinetic exchange models of markets, and propose an effective bridge between the microfoundation based on the maximization of the utility function and the non-conservative models. Both results are new in the context of econophysics.Maestrí

Casa Klumb: an issue of preservation and education

Early on the morning of November 11, 2020, we woke to news of the “fire that destroyed the Klumb House.” The somber story that detailed the complete erasure of the emblematic structure, under the custody of the administration of the University of Puerto Rico, at the express wish of the architect Henry Klumb, went viral and broke the Internet. The newspaper columns proliferated with a wide range of views on the issue. Leaving the essential question: Why did this happen