Generalized Schr\"odinger cat states and their classical emulation

We demonstrate that superpositions of coherent and displaced Fock states, also referred to as generalized Schr\"odinger cats cats, can be created by application of a nonlinear displacement operator which is a deformed version of the Glauber displacement operator. Consequently, such generalized cat states can be formally considered as nonlinear coherent states. We then show that Glauber-Fock photonic lattices endowed with alternating positive and negative coupling coefficients give rise to classical analogs of such cat states. In addition, it is pointed out that the analytic propagator of these deformed Glauber-Fock arrays explicitly contains the Wigner operator opening the possibility to observe Wigner functions of the quantum harmonic oscillator in the classical domain.Comment: 17 pages, 5 figure

Limited Self-control, Obesity, and the Loss of Happiness

Is obesity the consequence of an optimally chosen lifestyle or do people consume too much relative to their long-term preferences? The latter perspective accepts that people might face self-control problems when exposed to the immediate gratification from food. We exploit unique survey data for Switzerland in multinomial logit and ordered probit regressions to study (i) the covariates of obesity including indicators of self-control and (ii) the consequences of obesity on the subjective well-being of people with limited willpower. Our main finding is that obesity decreases the well-being of individuals who report having limited self-control, but not otherwise. © 2015 John Wiley & Sons, Ltd

Peer Gender and Mental Health

Adolescent mental health is key for later well-being. Yet, causal evidence on environmental drivers of adolescent mental health is scant. We study how an important classroom feature---the gender composition in compulsory-school---affects mental health. We use Swedish administrative data (N=576,285) to link variation in gender composition across classrooms within cohorts to mental health. We find that a higher share of female peers in a classroom increases the incidence of mental health diagnoses, particularly among boys. The effect persists into adulthood. Peer composition is thus an important and persistent driver of mental health

Rain, emotions and voting for the Status Quo

Do emotions affect the decision between change and the status quo? We exploit exogenous variation in emotions caused by rain and analyze data on more than 400 ballot propositions in Switzerland for the years 1958 to 2014 to address this question. The empirical tests are based on administrative ballot outcomes and individual postvote survey data. We find that rain decreases the share of votes for a change. Our robustness checks suggest that changes in the composition of the electorate or changes in information acquisition do not drive this result. In addition, we provide evidence that rain might have altered the outcome of several high-stake votes. We discuss the psychological mechanism and document that rain reduces the willingness to take risks, a pattern that is consistent with the observed reduction in the support of change

Tobacco sales prohibition and teen smoking

We evaluate one of the most prevalent prohibitory policies: banning the sales of tobacco to teens. We exploit the staggered introduction of sales bans across Switzerland and analyze rich data from 2001 to 2016. The estimates do not indicate an immediate or long-run systematic reduction in the overall prevalence of smoking because of sales bans. We also examine a range of behavioral mechanisms that are key to understand the consequences of prohibitory policies such as habit formation, social appeal of smoking, circumvention behavior, or risk perceptions. Among others, we find that teens circumvent the bans by getting cigarettes from peers. Moreover, teens consider smokers less cool when a sales ban is in place, but they do not consider smoking more dangerous

Tobacco Sales Prohibition and Teen Smoking

We evaluate one of the most prevalent prohibitory policies: banning the sales of tobacco to teens. We exploit the staggered introduction of sales bans across Switzerland and the European Union from 1990 to 2016. The estimates indicate a less than 1 percentage point reduction in teen smoking because of the bans. The reduction is substantially lower than the 5 percentage point reduction expected by health officials. We examine additional outcomes relevant to assessing any prohibitory policy. We find that teens circumvent the bans through peers. Moreover, they consider smokers less cool but do not think smoking is more dangerous

Overstrained citizens? The number of ballot propositions and the quality of the decision process in direct democracy

We study how the number of ballot propositions affects the quality of decision making in direct democracy, as reflected in citizens` knowledge, voting behavior, and attitudes toward democracy. Using three comprehensive data sets from Switzerland with over 3,500 propositions, we exploit variation in the number of federal and cantonal propositions. Voters know the most about the content of federal propositions when they are exclusively presented and less with a high number of concurrent cantonal propositions on the ballot. Across other outcomes we find no consistent indications that - for the observed variation in the exposure to popular votes - a high number of propositions impedes the quality of decision making in Swiss federal direct democracy. In the medium to longer term, more federal propositions on the ballot rather relate to higher perceived political influence and satisfaction with democracy

Spin-orbit coupling and electron spin resonance for interacting electrons in carbon nanotubes

We review the theoretical description of spin-orbit scattering and electron spin resonance in carbon nanotubes. Particular emphasis is laid on the effects of electron-electron interactions. The spin-orbit coupling is derived, and the resulting ESR spectrum is analyzed both using the effective low-energy field theory and numerical studies of finite-size Hubbard chains and two-leg Hubbard ladders. For single-wall tubes, the field theoretical description predicts a double peak spectrum linked to the existence of spin-charge separation. The numerical analysis basically confirms this picture, but also predicts additional features in finite-size samples.Comment: 19 pages, 4 figures, invited review article for special issue in J. Phys. Cond. Mat., published versio