ABSTRACT
On the tribunal view on experimentation, experiments are the place where empirical implications or numerical simulations of theoretical models are confronted with outcomes of measurements, the data. But that supposes that it is clear what the correct theoretical implications, the correct simulation conditions, and the correct data are. By contrast and in reaction to the ‘tribunal view’ on experimentation, this essay will show that experimental activity, first of all, plays an essential role in a task of clarification. It will show the elaboration of an experimental system as an interactive, creative, openended process and highlight its constructive contribution to the processes of modeling and simulating. This constructive role of experimental activity will be explored through the analysis of a particular episode in 20th-century fluid mechanics, presented in ‘Origin of the Controversy: The Discontinuity’, focusing specifically on two aspects. The first, discussed from ‘Conflicting Interpretations of the Discontinuity’ to ‘Simulation of the Wake’, will be introduced with a controversy regarding the characteristics of the phenomenon under investigation (‘Conflicting Interpretations of the Discontinuity’). The function of experimental activity will be to identify the conditions in which outcomes of measurements qualify as data that a putative model of the phenomenon would have to fit (‘Enter the Landau Model’ and ‘Intrinsic Characteristics and Relevant Parameters’) or a simulation would have to reproduce (‘Simulation of the Wake’). The second, discussed in ‘Experimental Contribution to Conceptual Understanding’, is conceptual clarification and innovation. In that episode, a long controversy over the identification of some structural characteristics of the target phenomenon would finally lead to questioning implicit presuppositions about the conditions of correct measurement. The answer to these questions through experimentation would take the form of a redefinition of concepts central to the understanding of the phenomenon and the conditions of its occurrence.
