Quantum Cultures during the Prehistory of Quantum Gravity: Léon Rosenfeld's Early Contributions to Quantum Gravity

In this paper we consider the prehistory of quantum gravity (1916–1930) from two perspectives. First, we investigate how this research field constituted itself and we propose for the first time a red thread to trace its evolution in this earliest period. Second, we focus on a case study: the earliest work of Léon Rosenfeld. In 1927 he tried to merge wave mechanics with general relativity in the context of a five‐dimensional universe. We describe how Oskar Klein, Louis de Broglie, and Théophile De Donder influenced Rosenfeld's work and analyze how and why Rosenfeld attempted to reconcile Einstein's theory with quantum phenomena. We argue that Rosenfeld investigated for the first time the corrections to a classical space‐time metric generated by a quantum source. As far as we know, Rosenfeld's approach has been largely ignored until today: he himself considered it “an accident.” After having reconsidered its connection with de Broglie's ideas and Rosenfeld's interpretation of the wave function in 1927, we argue that Rosenfeld's work can be interpreted as a first attempt to introduce the pilot‐wave theory in the context of quantum gravity and we infer that this was one of the reasons that ruled it out.     

A Late Roman ceramic production from Pompeii

The Via Lepanto site is one of the best examples showing how the Vesuvian region was partially reconstructed and earlier re-occupied after Vesuvius's eruption in the year 79 AD. The large amount of ceramic finds illustrates the typology in use in this area during the IV and V century AD. Analyses were focused on table and cooking ware productions. Archaeometric data were obtained using chemical and minero-petrographical methods (OM, XRD, XRF and SEM). Grain size measurements using Image Analyses on thin sections and a geochemical comparison with clayey deposits outcropping in the Campania region permitted the identification of the raw materials used for these pottery productions. XRD and SEM completed the data set, establishing the protocols used for pottery production in the Pompeii area during Late Roman period. The Via Lepanto site was part of an exchange network of markets with a periodic frequency, where locally produced and imported pottery was sold, indicating a flourishing network of exchanges spanning short, medium and long distances.     

Social decision-making driven by artistic explore–exploit tension

We studied social decision-making in the rule-based improvisational dance There Might Be Others, where dancers make in-the-moment compositional choices. Rehearsals provided a natural test-bed with communication restricted to non-verbal cues. We observed a key artistic explore–exploit tension in which the dancers switched between exploitation of existing artistic opportunities and riskier exploration of new ones. We investigated how the rules influenced the dynamics using rehearsals together with a model generalized from evolutionary dynamics. We tuned the rules to heighten the tension and modelled nonlinear fitness and feedback dynamics for mutation rate to capture the observed temporal phasing of the dancers' exploration-versus-exploitation. Using bifurcation analysis, we identified key controls of the tension and showed how they could shape the decision-making dynamics of the model much like turning a ‘dial’ in the instructions to the dancers could shape the dance. The investigation became an integral part of the development of the dance.     

A new phoenix? Large plants regeneration policies in Italy

The fall of employment in manufacturing that the world's most advanced economies have been experiencing in the past 40 years has triggered a number of policies, undertaken in several countries. In this paper, we evaluate the effectiveness of a place-based policy, carried out in Italy, aimed at both generating private investments and increasing employment in areas affected by deep industrial decline. By means of an instrumental variable identification strategy, we show that the program has been largely unsuccessful.     

Film production incentives,employment transformation and domestic expenditure in South Africa: visualizing subsidy effectiveness

In 2004 the South African Department of Trade and Industry (DTI) introduced a Film and Television Production Rebate Programme. In order to qualify for the rebate, certain criteria have to be met including success in job creation and skills development within the industry, alongside a particular focus on the percentage of ‘historically disadvantaged individuals’ employed. This study sets out the issues associated with evaluating success in meeting these various criteria and is, to the best of our knowledge, the first study to apply multi-criteria visualization techniques to inform the evaluation of public subsidy effectiveness. The ‘PROMETHEE’ method is applied and apart from presenting project performance in a visually intuitive manner, the approach helps to clarify patterns of relative success, show where policy objectives are competing, and to identify project exemplars for more efficiently guiding future public support in the sector.