Uma análise do contexto de criação do processo URCA: diversidade epistêmica e circulação transnacional

Abstract

This dissertation examines the historical episode surrounding the development of the URCA process, within the context of the collaboration between George Gamow and Mário Schenberg, situating it within the broader consolidation of theoretical models of stellar evolution and gravitational collapse in the first half of the twentieth century. The study investigates how this episode fits into the conceptual transformations that took place from the early 1900s to the mid-1940s, a period marked by the incorporation of nuclear physics, relativistic statistical mechanics, and new energy-transport mechanisms into theoretical astrophysics. Particular attention is devoted to the specific contribution of Mário Schenberg, a Brazilian physicist whose participation in the formulation of the neutrino energy-loss mechanism played a significant role in early attempts to explain the collapse of massive stars and the phenomena associated with supernovae. By reconstructing this collaboration historically, the dissertation analyzes how the interaction between Gamow—a Russian-born, American-based physicist working within hegemonic centers of international science—and Schenberg, whose scientific trajectory emerged from a peripheral context, contributes to a deeper understanding of how nationality, educational trajectories, and geopolitical positioning shaped both individual contributions and the collective dynamics of scientific knowledge production. Accordingly, the general objective of this research is to identify and analyze aspects of the Nature of Science (NoS) that emerge from this historical episode, with particular emphasis on epistemic pluralism, the international circulation of ideas, and the symbolic hierarchies operating within the scientific community. More specifically, the study examines how Schenberg’s participation in the development of the URCA process allows for a critical reassessment of conceptions that portray science as neutral, purely meritocratic, or guided exclusively by internal criteria of rationality. Methodologically, the dissertation employs a historical–epistemological analysis of secondary sources, including scientific articles and personal correspondence, in order to elucidate both the processes of theoretical construction and the social conditions that shaped this episode. The analysis demonstrates that the development of the URCA process involved the articulation of diverse styles of thought, heuristic resources, and cultural contexts, while simultaneously revealing mechanisms of exclusion, stereotypes, and hierarchies associated with the geographical origin and nationality of the scientists involved. It is therefore concluded that this episode constitutes a historically significant case not only for understanding stellar evolution, but also for recognizing Mário Schenberg’s contribution to the history of astrophysics, and for conceiving science as a collective, creative, and transnational practice, marked by tensions between epistemological universalism and geopolitical inequalities.