Publications

Previous research has established that men are more likely to vote for populist radical right parties (PRRPs) than women. This article shows how cross-national and temporal variations in PRRPs’ electoral success interact with individuals’ risk propensity to affect this gender gap. We hypothesize that gender differences in the electoral support of PRRPs stem from disparities in risk-taking. We conceptualize risk in terms of two components, social and electoral, and demonstrate that women are more risk-averse regarding both. Our analysis is based on public opinion data from 14 countries (2002–2016) combined with macro-level data on PRRPs’ past parliamentary fortunes. To distinguish between the social and the electoral component in risk-taking, we use the illustrative case study of Germany. Findings demonstrate that gender differences in risk-taking and, by implication, the differences between women’s and men’s responses to the electoral context, are key to understanding the voting gender gap.

This paper characterizes the preferences over bounded infinite utility streams that satisfy the time value of money principle and an additivity property, and preferences that in addition are impatient. Based on this characterization, the paper introduces a concept of optimization that is robust to a small imprecision in the specification of the preference, and proves that the set of feasible streams of payoffs of a finite Markov decision process admits such a robust optimization.

Causative constructions come in lexical and periphrastic variants, exemplified in English by Sam killed Lee and Sam caused Lee to die. While use of the former, the lexical causative, entails the truth of the latter, an entailment in the other direction does not hold.  The source of this asymmetry is commonly ascribed to the lexical causative having an additional prerequisite of “direct causation", such that the causative relation holds between a contiguous cause and effect (Fodor 1970, Katz 1970).  However, this explanation encounters both empirical and theoretical problems (Nelleman & van der Koot  2012). To explain the source of the directness inferences (as well as other longstanding puzzles), we propose a formal analysis based on the framework of Structural Equation Models (SEMs) (Pearl 2000) which provides the necessary background for licensing causal inferences. Specifically, we provide a formalization of a 'sufficient set of conditions' within a model and demonstrate its role in the selectional parameters of causative descriptions. We argue that “causal sufficiency” is not a property of singular conditions, but rather sets of conditions, which are individually necessary but only sufficient when taken together (a view originally motivated in the philosophical literature by Mackie 1965). We further introduce the notion of a “completion event” of a sufficient set, which is critical to explain the particular inferential profile of lexical causatives. 

This paper introduces a systematic way of analyzing the semantics of causative linguistic expressions, and of how causal relations are expressed in natural languages. The starting point for this broad agenda is to provide an explanation for the asymmetrical inferential relationship between two causative constructions: change-of-state (CoS) verbs and the verb cause, commonly ascribed to the former having an additional prerequisite of direct causation. The direct causation hypothesis, however, is fraught with empirical and theoretical challenges. At the theoretical level, capturing the felicity conditions specific to CoS verbs and the notion of direct causation requires a means of modelling complex causal structures. This is on no account a trivial task, as it necessitates, inter alia, modelling causation in a way that is germane to the linguistic expressions designating such relations. Hence, the main objective of this paper is to develop a framework for modelling the  semantics of causal statements. For this purpose, this paper makes use of the framework
of Structural Equation Modelling (SEM), and it demonstrates how this approach provides tools for a rigorous model-theoretic treatment of the differential semantics of causal  expressions. This paper introduces formal logical definitions of different types of conditions  using SEM networks, and show how this proposal and the formal tools it employs allow us to make sense of the asymmetric entailment relationship between the two constructions. In our proposal, CoS verbs do not require contiguity between cause and effect at all, but instead they require that its subject is set by default to a participant in completion event, the event which “completes” a sufficient set of conditions, such that following this event (but not before) the values of the set of conditions in the sufficient set entail that the effect occurs. According to this, the intuition of direct causation arises (epiphenomenally) from contrasting CoS verbs with overt cause sentences: the stronger selection pattern of the former - which requires a completion event - may exclude more temporally distant conditions, while the latter admits any necessary condition. 

We report high-level calculations of the excited states of [2,2]-paracyclophane (PCP), which was recently investigated experimentally by ultrafast pump-probe experiments on oriented single crystals [Haggag et al., ChemPhotoChem 6 e202200181 (2022)]. PCP, in which the orientation of the two benzene rings and their range of motion are constrained, serves as a model for studying benzene exciplex formation. The character of the excimer state and the state responsible for the brightest transition are similar to those in benzene dimer. The constrained structure of PCP allows one to focus on the most important degree of freedom, the inter-ring distance. The calculations explain the main features of the transient absorption spectral evolution. This brightest transition of the excimer is polarized along the inter-fragment axis. The absorption of light polarized in the plane of the rings reveals the presence of other absorbing states of Rydberg character, with much weaker intensities. We also report new transient absorption data obtained by a broadband 8 fs pump, which time-resolve strong modulations of the excimer absorption. The combination of theory and experiment provides a detailed picture of the evolution of the electronic structure of the PCP excimer in the course of a single molecular vibration.

This study overviews and extends a recently developed stochastic finite-temperature Kohn-Sham density functional theory to study warm dense matter using Langevin dynamics, specifically under periodic boundary conditions. The method's algorithmic complexity exhibits nearly linear scaling with system size and is inversely proportional to the temperature. Additionally, a novel linear-scaling stochastic approach is introduced to assess the Kubo-Greenwood conductivity, demonstrating exceptional stability for DC conductivity. Utilizing the developed tools, we investigate the equation of state, radial distribution, and electronic conductivity of Hydrogen at a temperature of 30,000K. As for the radial distribution functions, we reveal a transition of Hydrogen from gas-like to liquid-like behavior as its density exceeds 4 g/cm³. As for the electronic conductivity as a function of the density, we identified a remarkable isosbestic point at frequencies around 7eV, which may be an additional signature of a gas-liquid transition in Hydrogen at 30,000K.

 An absorbing game is a two-person zero-sum repeated game. Some of the entries are ``absorbing'' in the sense that, following the play of an absorbing entry, with positive probability all future payoffs are equal to that entry's payoff. The outcome of the game is the long-run average payoff.
 We prove that a two-person zero-sum absorbing game, with either finite or compact action sets, has, for each e>0, e-optimal strategies with finite memory. In fact, we show that there is an e-optimal strategy that depends on the clock and three states of memory.