Dispersion relation of the non-linear Klein-Gordon equation through a variational method

We derive approximate expressions for the dispersion relation of the nonlinear Klein-Gordon equation in the case of strong nonlinearities using a method based on the Linear Delta Expansion. All the results obtained in this article are fully analytical, never involve the use of special functions, and can be used to obtain systematic approximations to the exact results to any desired degree of accuracy. We compare our findings with similar results in the literature and show that our approach leads to better and simpler results.Comment: 10 pages, 3 figures, matches published versio

Effect of the Quark-Gluon Vertex on Dynamical Chiral Symmetry Breaking

In this work we investigate how the details of the quark-gluon interaction vertex affect the quantitative description of chiral symmetry breaking and dynamical mass generation through the gap equation. We employ the Maris-Tandy (MT) and Qin-Chang (QC) models for the gluon propagator and the effective strong running coupling. The gap equation is solved by employing several vertex Ans${\rm \ddot{a}}$tze which have been constructed in order to implement some of the key aspects of a gauge field theory such as gauge invariance and multiplicative renormalizability. We find that within a small variation of MT and QC model parameters, all truncations point towards the same quantitative pattern of chiral symmetry breaking, the running quark mass function, ensuring the robustness of this approach.Comment: 12 page

‘News Reporting on Possible Origins of the COVID-19 Pandemic: A critical review and case study’

This project is a critical analysis of news reports that discuss the potential origins of the \u27COVID-19\u27 pandemic for the purposes of identifying themes and trends in the actual reporting. Around 500 news reports published in the U.S. were analyzed and over 100 of them were selected for the critical review. Articles were found using \u27Access News Archive\u27 and Google search engine. Original methods for analyzing and reviewing articles were developed and used. A case study is included aside from the review which focuses specifically on trends in fact-check reporting during the pandemic

Pengembangan Mobile Learning Berbasis Android Pada Mata Pelajaran Produk Kreatif Dan Kewirausahaan Sekolah Menengah Kejuruan

Tujuan penelitian dari pengembangan ini yaitu untuk mengeksplorasi pengembangan dan kelayakan media mobile learning berbasis android pada pelajaran produk kreatif dan kewirausahaan BDP kelas XI di SMKN 1 Surabaya. Metode penelitian yang digunakan ialah Research And Development dengan metode pengembangannya menggunakan 4D yang memiliki empat tahap yaitu tahap mendefinisikan, tahap merancang, tahap mengembangkan, dan tahap penyebaran. Dalam penelitian ini instrumen atau peralatan yang digunakan terdiri dari lembar penilaian pakar materi 1 dan 2, lembar telaah pakar media, dan angket respon siswa SMK Negeri 1 Surabaya. Penelitian dilakukan di SMKN1 Surabaya dalam uji percobaan kelompok kecil yang terdiri dari 10 siswa kelas XI BDP 1 dilanjutkan dengan uji lapangan sebanyak 35 siswa dengan menggunakan kelas XI BDP 2. Hal tersebut dibuktikan dengan hasil dari validasi pakar materi 1 yang persentase mencapai 92%, validasi pakar materi 2 sebesar 98%, validasi pakar media sebanyak 80%, dan uji coba kelompok kecil memperoleh 80% serta uji coba lapangan memperoleh sebesar 87%