The usual theoretical treatments of the near-threshold pp\ensuremath{\rightarrow}pp${\mathrm{\ensuremath{\pi}}}^{0}$ reaction are based on various phenomenological Lagrangians. In this work we examine relationship between these approaches and a systematic chiral perturbation method. Our calculation indicates that pion rescattering term should be significantly enhanced as compared with traditional treatment, have substantial energy momentum dependence. An important consequence energy-momentum...

Working in the SU(2) flavor version of NJL model, we study effect taking a finite system volume on strongly interacting quarks, and, particular, location chiral phase transition and CEP. We consider two shapes for volume, spherical cubic regions with different sizes boundary conditions. To analyze QCD diagram, use novel criterion to crossover zone. A comparison between results obtained from several conditions is carried out. method Multiple Reflection Expansion determine density states three...

Water is a precious and contested resource in Colorado, the seventh driest state United States. Throughout its geologic history, this territory has seen innumerable configurations spearheaded mostly by uplifting erosion. During human land also several important infrastructural other changes, especially as they relate to water usage. Responding these conditions, pedagogical exercise recontextualized “nature” designing for with geological systems. The studio combined models of design-build...

En este artículo se presentan algunos aspectos históricos del desarrollo Principio de Mínima Acción y establecen los métodos matemáticos principios variacionales que permiten implementar Principio. Este lleva implícita en su esencia estructura, una las ideas más fundamentales profundas han establecido para entender a la naturaleza. El aspecto central es el hecho fenómenos naturales necesario partir relacionadas con simplicidad, orden, perfección optimización recursos dispone naturaleza...

It was found that the most simple analysis in linear σ- model, where sigma meson couples vacuum to two virtual pions, predicted typical values for σ-mass and total decay width as 486+/-7MeV 340+/-20MeV respectively. demonstrate, via statistical analysis, experimental reported by Fermilab (E791) Collaboration represents approximately 56% of model together with Breit-Wigner formalism. Additional, it created spectral function, terms σ-meson regularized self-energy, which is consistently...

In this work, we study the temperature and chemical potential dependence of masses sigma pion mesons as well quark condensate by using a SU(2) flavor version Nambu–Jona–Lassino model, introducing prescription that mimics confinement. We have found increases, mass shifts down, while remains almost constant. On other hand, decreases increases. also analyzed spectral function meson, from which observe at low values T [Formula: see text] an absence peak. Furthermore, Mott is reached, its value...

We study the changes of mass and width sigma meson in framework Linear Sigma Model at finite temperature, one-loop approximation. have found that as temperature increases, shifts down. also analyzed [Formula: see text]-spectral function we observe an enhancement threshold which is a signature partial restoration chiral symmetry, interpreted tendency to phase transition. Additionally, studied sigma, when takes place, for different values mass. there brief enlargement followed by abrupt fall...

La geometría euclidiana está fundada en cinco postulados que se presentan como verdades evidentes, es decir, de las no puede dudar. Por mucho tiempo pensó podía existir una diferente a la Euclides, sin embargo, dudas sobre independencia del quinto postulado respecto los otros cuatro, abrió el camino para desarrollo nuevas geometrías. El impacto filosófico geometrías no-euclidianas provocó revolución pensamiento matemático transformando matemática ciencia aún más abstracta y abriendo...

Abstract In the context of SU(2) quark flavor version Nambu–Jona-Lasinio model extended by Polyakov loop, effect regularization scheme on quantum chromodynamics phase structure at finite volume was studied. The way in which diagram changes with type loop potential considered this study also investigated. study, a polynomial and logarithmic were used. On other hand, that satisfies thermodynamics properties such as Stefan–Boltzmann limit chosen.

We study two coupling constants reported as predictions of the sigma model. obtain an spectral distribution, in terms \sigma meson regularized self- energy one loop order, which is consistently with Breit-Wigner converging to values mass and width this scalar resonance given experimental results by E791 Collaboration at Fermilab BES Beijing Electron Positron Collider. conclude that restricted be on range 453MeV < m\sigma 490MeV its 238MeV-354MeV or 354MeV 415MeV 167.5 \Gamma\sigma 347MeV MeV.

Se calcula la masa física del mesón escalar s utilizando su función espectral. La espectral es calculada considerando que partícula sigma se acopla a un par de piones virtuales π+-π-. El propagador σ evaluado después calcular autoenergía, cuya parte real dada por una integral divergente requiere ser regularizada. Al realizar regularización mediante el proceso substracción simple en relación dispersión, obtiene expresión analítica cerrada para lo permite evaluar forma cerrada. Definiendo como...

Stephen Hawking, considerado uno de los científicos más notables en campos la cosmología y astrofísica últimos cincuenta años, nace ciudad Oxford, Inglaterra el 8 enero 1942 seno una familia clase media. Su vida constituye un ejemplo tenacidad, optimismo entrega a actividad científica, lo cual ha sido motivo inspiración para muchos jóvenes que se han inclinado por estudiar carreras científicas.

En este artículo se analiza la evolución que ha tenido el concepto tiempo en ciencia. El como un elemental forma nuestra mente simplemente resultado de existencia, y nos permite ordenar los acontecimientos, ser uno más misteriosos difíciles comprender. lo introdujo Newton ciencia parámetro absoluto no resulta afectado por nada, usándolo recurso matemático para describir fenómenos naturaleza. Posteriormente, Einstein encontraría es una cantidad absoluta, sino depende del observador mida....