This work deals with the presence of defect structures in models described by a real scalar field in a diversity of scenarios. The defect structures that we consider are static solutions of the equations of motion that depend on a single spatial dimension. We search for different models, which support the same defect solution, with the very same energy density. We work in flat spacetime, where we introduce and investigate a new class of models. We also work in curved spacetime, within the braneworld context, with a single extra dimension of infinite extent, and there we show how the brane is formed from the static field configuration.

We study cosmological models described by a single real scalar field. We work within the firstorder framework, and we show how the first-order equations simplify the investigation, leading to a direct search of twinlike theories. The procedure is used to introduce distinct models that support the same first-order equations, with the very same energy densities and pressure in flat spacetime. The presence of curvature forbids the construction of twinlike models in the cosmological scenario here investigated.

<p>A flauta é um instrumento musical classificado como instrumento de sopro. Dentre os diversos tipos, a flauta transversal tem esse nome devido ao sopro ser transversal ao comprimento da flauta. Neste artigo, analisamos o espectro sonoro desse tipo de flauta, identificamos os harmônicos mais intensos na formação do timbre do instrumento para diversas notas musicais da escala diatônica, e reproduzimos a forma da onda sonora resultante com base no espectro.</p>