| 1. |
- Thomas, HS, et al.
(författare)
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- 2019
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swepub:Mat__t
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| 2. |
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| 3. |
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| 4. |
- Eriksson, G., et al.
(författare)
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Finite-size effects in the dynamics of few bosons in a ring potential
- 2018
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Ingår i: Journal of Physics B: Atomic, Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 51:3
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Tidskriftsartikel (refereegranskat)abstract
- We study the temporal evolution of a small number N of ultra-cold bosonic atoms confined in a ring potential. Assuming that initially the system is in a solitary-wave solution of the corresponding mean-field problem, we identify significant differences in the time evolution of the density distribution of the atoms when it instead is evaluated with the many-body Schrödinger equation. Three characteristic timescales are derived: the first is the period of rotation of the wave around the ring, the second is associated with a 'decay' of the density variation, and the third is associated with periodic 'collapses' and 'revivals' of the density variations, with a factor of separating each of them. The last two timescales tend to infinity in the appropriate limit of large N, in agreement with the mean-field approximation. These findings are based on the assumption of the initial state being a mean-field state. We confirm this behavior by comparison to the exact solutions for a few-body system stirred by an external potential. We find that the exact solutions of the driven system exhibit similar dynamical features.
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| 5. |
- Akay, Alpaslan, 1975, et al.
(författare)
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Cooperation and punishment: The effect of religiosity and religious festival
- 2015
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Ingår i: Economics Letters. - : Elsevier BV. - 0165-1765. ; 130, s. 43-46
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Tidskriftsartikel (refereegranskat)abstract
- This paper examines how a religious festival (Ramadan) and the degree of religiosity affect cooperation and costly punishment in a public goods experiment. We find significantly higher cooperation levels outside the festival among less religious people. This behavior is consistent with a substitution effect between religious and non-religious activities. © 2015 Elsevier B.V.
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| 6. |
- Akay, Alpaslan, 1975, et al.
(författare)
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LIFE SATISFACTION, PRO-ACTIVITY AND EMPLOYMENT
- 2021
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Ingår i: Singapore Economic Review. - : World Scientific Pub Co Pte Lt. - 0217-5908 .- 1793-6837.
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Tidskriftsartikel (refereegranskat)abstract
- Using longitudinal data from the German Socio-Economic Panel (GSOEP), this paper investigates how pro-active time-use (e.g., in sports/arts/socializing) relates to subjective well-being of the unemployed and their probability of finding a new job. Allowing for a variety of socio-demographic and -economic observed characteristics, we find that pro-activity is negatively associated with the well-being loss upon unemployment. That is, the negative unemployment shock on their well-being is mitigated through various stress-reducing activities including, in particular, art participation, socializing, going on trips and visiting a church. We also find that the probability of returning to the labor market later is positively associated with pro-activity during the unemployment period. The results are robust to various checks including estimators, measures and individual personality characteristics which can correlate with time-use activities.
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| 7. |
- Akay, Alpaslan, 1975, et al.
(författare)
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Personality and positionality-evidence from survey experiments with alternative goods
- 2020
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Ingår i: Eurasian Business Review. - : Springer Science and Business Media LLC. - 1309-4297 .- 2147-4281. ; 2020:10, s. 123-156
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Tidskriftsartikel (refereegranskat)abstract
- This paper employs survey experiments to examine the relationship between personality characteristics and positional concerns across a wide range of "goods", e.g., income and market value of a car, and "bads", e.g., infant mortality and poverty rates. Personality traits are measured using the five-factor model (Big-5), the locus of control, and reciprocity. We demonstrate that there are significant relationships between personality types and positional concerns, which differ both by the type of personality and by the nature of a good. The results are highly consistent with the predictions presented in the field of personality psychology. That is, while agreeableness is negatively associated, conscientiousness, neuroticism, and external locus of control are positively associated with positional concerns for most goods. Importantly, there is also a substantial heterogeneity in the mean degree of positional concerns across the low and high values of most personality characteristics and goods.
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| 8. |
- Akay, Alpaslan, 1975, et al.
(författare)
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Standing in Others' Shoes: Empathy and Positional Behavior
- 2019
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Ingår i: Frontiers in Psychology. - Gothenburg : Frontiers Media SA. - 1664-1078. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- Studies show that people are concerned with other people's consumption position in a varying degree with respect to the type of goods consumed and individual characteristics. Using both survey experiments and a large survey of subjective well-being (SWB) dataset, this paper aims to investigate the association between the degree of empathic capacity and positional concerns for consumption items involving pleasure and pain. The paper exploits both empathy quotient (EQ) and interpersonal reactivity index (IRI) measures of empathic capacity, i.e., dispositional empathy, which are sufficient measures capturing affective and cognitive aspects of empathy. Positional concerns are identified directly using a series of stated choice experiments and indirectly using the SWB approach. The main result of the paper is that positional concerns vary substantially with the levels of empathic capacity. Both EQ and IRI are found to be positively associated with positional concerns for "goods" (e.g., after-tax income, market value of a luxury car), reflecting a degree of self-regarded feelings and behavior to reduce personal distress, and negatively associated with positional concerns for "bads" (e.g., working hours and poverty rates), reflecting a degree of other-regarding feelings and behavior. The results are robust with respect to various checks including statistical specifications, reference groups, and omitted variables (e.g., prosocial behavior and competitivity) that could bias the results.
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| 9. |
- Akay, A., et al.
(författare)
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The effect of religiosity and religious festivals on positional concerns - an experimental investigation of Ramadan
- 2013
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Ingår i: Applied Economics. - : Informa UK Limited. - 0003-6846 .- 1466-4283. ; 45:27, s. 3914-3921
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Tidskriftsartikel (refereegranskat)abstract
- This article examines the effect of religion on positional concerns using survey experiments. We focus on two of the dimensions of religion degree of religiosity and religious festivals. By conducting the experiments during both the most important day of Ramadan (the Night of Power) and a day outside Ramadan, we find that Ramadan overall has a small and negative impact on positional concerns. Detailed analyses based on the sorting of individuals degree of religiosity reveal that the decrease in the degree of positional concerns during Ramadan is mainly explained by a decrease in positionality among individuals with a low degree of religiosity.
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| 10. |
- Cremon, Jonas, et al.
(författare)
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Rotating Bose-Einstein condensates: Closing the gap between exact and mean-field solutions
- 2015
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Ingår i: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 91:3
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Tidskriftsartikel (refereegranskat)abstract
- When a Bose-Einstein-condensed cloud of atoms is given some angular momentum, it forms vortices arranged in structures with a discrete rotational symmetry. For these vortex states, the Hilbert space of the exact solution separates into a "primary" space related to the mean-field Gross-Pitaevskii solution and a "complementary" space including the corrections beyond mean field. Considering a weakly interacting Bose-Einstein condensate of harmonically trapped atoms, we demonstrate how this separation can be used to close the conceptual gap between exact solutions for systems with only a few atoms and the thermodynamic limit for which the mean field is the correct leading-order approximation. Although we illustrate this approach for the case of weak interactions, it is expected to be more generally valid.
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