Proof-theoretic Analysis of Rationality for Strategic Games with Arbitrary Strategy Sets

In the context of strategic games, we provide an axiomatic proof of the statement Common knowledge of rationality implies that the players will choose only strategies that survive the iterated elimination of strictly dominated strategies. Rationality here means playing only strategies one believes to be best responses. This involves looking at two formal languages. One is first-order, and is used to formalise optimality conditions, like avoiding strictly dominated strategies, or playing a best response. The other is a modal fixpoint language with expressions for optimality, rationality and belief. Fixpoints are used to form expressions for common belief and for iterated elimination of non-optimal strategies.Comment: 16 pages, Proc. 11th International Workshop on Computational Logic in Multi-Agent Systems (CLIMA XI). To appea

Different effects of sevoflurane, desflurane, and isoflurane on early and late left ventricular diastolic function in young healthy adults†

Background Knowledge on the effects of volatile anaesthetics on left ventricular (LV) diastolic function in humans in vivo is limited. We tested the hypothesis that sevoflurane, desflurane, and isoflurane do not impair LV diastolic function in young healthy humans. Methods Sixty otherwise healthy subjects (aged 18-48 yr) undergoing minor procedures under general anaesthesia were studied. After randomization for the anaesthetic, transthoracic echocardiographic examinations were performed at baseline and under anaesthesia with 1 minimum alveolar concentration (MAC) of the volatile anaesthetics during spontaneous breathing and intermittent positive pressure ventilation (IPPV). Peak early (E′) and late (A′) diastolic velocities of the mitral annulus were studied as the main echocardiographic indicators of diastolic function. Results During anaesthesia with 1 MAC under spontaneous breathing, E′ increased with desflurane (P<0.001), was not significantly different with isoflurane (P=0.030), and decreased with sevoflurane (P=0.006). During IPPV, E′ was similar to baseline with desflurane (P=0.550), insignificantly decreased with isoflurane (P=0.029), and decreased with the sevoflurane group (P<0.001). In contrast, A′ was similarly reduced in all groups during spontaneous breathing without further changes during IPPV. Haemodynamic changes were comparable in all study groups. Conclusions The findings of this in vivo study indicate that desflurane and isoflurane, and most likely sevoflurane, have no relevant direct negative effect on early diastolic relaxation in young healthy humans. In contrast, all three volatile anaesthetics appear to impair late diastolic LV filling during atrial contraction. Trial Registration #: NCT002445

Buffer-gas induced absorption resonances in Rb vapor

We observe transformation of the electromagnetically induced transparency (EIT) resonance into the absorption resonance in a $\Lambda$ interaction configuration in a cell filled with $^{87}$Rb and a buffer gas. This transformation occurs as a one-photon detuning of the coupling fields is varied from the atomic transition. No such absorption resonance is found in the absence of a buffer gas. The width of the absorption resonance is several times smaller than the width of the EIT resonance, and the changes of absorption near these resonances are about the same. Similar absorption resonances are detected in the Hanle configuration in a buffered cell.Comment: 11 pages, 15 figures; 13 pages, 17 figures, added numerical simulatio

Experimental Implementation of the Deutsch-Jozsa Algorithm for Three-Qubit Functions using Pure Coherent Molecular Superpositions

The Deutsch-Jozsa algorithm is experimentally demonstrated for three-qubit functions using pure coherent superpositions of Li$_{2}$ rovibrational eigenstates. The function's character, either constant or balanced, is evaluated by first imprinting the function, using a phase-shaped femtosecond pulse, on a coherent superposition of the molecular states, and then projecting the superposition onto an ionic final state, using a second femtosecond pulse at a specific time delay

Do people really want to be nudged towards healthy lifestyles?

This paper assesses Thaler and Sunstein’s claim that policies that nudge individuals towards healthy lifestyles promote the welfare of those individuals, as judged by themselves. I argue that Thaler and Sunstein switch between two different interpretations of that clause. One interpretation gives the clause a wide range of applicability, but drains it of its content as a repudiation of paternalism. The other interpretation makes it more meaningful to say that people want to make the choices they are being nudged towards, but applies to a much narrower range of cases than Thaler and Sunstein have in mind

Reinstated episodic context guides sampling-based decisions for reward.

How does experience inform decisions? In episodic sampling, decisions are guided by a few episodic memories of past choices. This process can yield choice patterns similar to model-free reinforcement learning; however, samples can vary from trial to trial, causing decisions to vary. Here we show that context retrieved during episodic sampling can cause choice behavior to deviate sharply from the predictions of reinforcement learning. Specifically, we show that, when a given memory is sampled, choices (in the present) are influenced by the properties of other decisions made in the same context as the sampled event. This effect is mediated by fMRI measures of context retrieval on each trial, suggesting a mechanism whereby cues trigger retrieval of context, which then triggers retrieval of other decisions from that context. This result establishes a new avenue by which experience can guide choice and, as such, has broad implications for the study of decisions

Spin Relaxation Resonances Due to the Spin-Axis Interaction in Dense Rubidium and Cesium Vapor

Resonances in the magnetic decoupling curves for the spin relaxation of dense alkali-metal vapors prove that much of the relaxation is due to the spin-axis interaction in triplet dimers. Initial estimates of the spin-axis coupling coefficients for the dimers are 290 MHz for Rb; 2500 MHz for Cs.Comment: submitted to Physical Review Letters, text + 3 figure

Structure of the mirror nuclei 9^9Be and 9^9B in a microscopic cluster model

The structure of the mirror nuclei $^9$Be and $^9$B is studied in a microscopic $\alpha+ \alpha+ n$ and $\alpha+ \alpha+ p$ three-cluster model using a fully antisymmetrized 9-nucleon wave function. The two-nucleon interaction includes central and spin-orbit components and the Coulomb potential. The ground state of $^9$Be is obtained accurately with the stochastic variational method, while several particle-unbound states of both $^9$Be and $^9$B are investigated with the complex scaling method.The calculation for $^9$Be supports the recent identification for the existence of two broad states around 6.5 MeV, and predicts the $\frac{3}{2}^{-}_2$ and $\frac{5}{2}^{-}_2$ states at about 4.5 MeV and 8 MeV, respectively. The similarity of the calculated spectra of $^9$Be and $^9$B enables one to identify unknown spins and parities of the $^9$B states. Available data on electromagnetic moments and elastic electron scatterings are reproduced very well. The enhancement of the $E$1 transition of the first excited state in $^9$Be is well accounted for. The calculated density of $^9$Be is found to reproduce the reaction cross section on a Carbon target. The analysis of the beta decay of $^9$Li to $^9$Be clearly shows that the wave function of $^9$Be must contain a small component that cannot be described by the simple $\alpha+ \alpha+ n$ model. This small component can be well accounted for by extending a configuration space to include the distortion of the $\alpha$-particle to $t+p$ and $h+n$ partitions.Comment: 24 page