| 1. |
- Andersson, Nils, et al.
(författare)
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Lagrangian perturbation theory for a superfluid immersed in an elastic neutron star crust
- 2011
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Ingår i: Monthly notices of the Royal Astronomical Society. - Oxford : Blackwell Scientific Publications. - 0035-8711 .- 1365-2966. ; 416:1, s. 118-132
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Tidskriftsartikel (refereegranskat)abstract
- The inner crust of mature neutron stars, where an elastic lattice of neutron-rich nuclei coexists with a neutron superfluid, impacts on a range of astrophysical phenomena. The presence of the superfluid is key to our understanding of pulsar glitches, and is expected to affect the thermal conductivity and hence the evolution of the surface temperature. The coupling between crust and superfluid must also be accounted for in studies of neutron star dynamics, discussions of global oscillations and associated instabilities. In this paper we develop Lagrangian perturbation theory for this problem, paying attention to key issues like superfluid entrainment, potential vortex pinning, dissipative mutual friction and the star's magnetic field. We also discuss the nature of the core-crust interface. The results provide a theoretical foundation for a range of interesting astrophysical applications.
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| 2. |
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| 3. |
- Glampedakis, Kostas, et al.
(författare)
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Ambipolar diffusion in superfluid neutron stars
- 2011
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Ingår i: Monthly notices of the Royal Astronomical Society. - : Royal Astronomical Society. - 0035-8711 .- 1365-2966. ; 413:3, s. 2021-2030
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- In this paper we reconsider the problem of magnetic field diffusion in neutron star cores. We model the star as consisting of a mixture of neutrons, protons and electrons, and allow for particle reactions and binary collisions between species. Our analysis is in much the same spirit as that of Goldreich & Reisenegger (1992), and we content ourselves with rough estimates of magnetic diffusion timescales, rather than solving accurately for some particular field geometry. However, our work improves upon previous treatments in one crucial respect: we allow for superfluidity in the neutron star matter. We find that the consequent mutual friction force, coupling the neutrons and charged particles, together with the suppression of particles collisions and reactions, drastically affect the ambipolar magnetic field diffusion timescale. In particular, the addition of superfluidity means that it is unlikely that there is ambipolar diffusion in magnetar cores on the timescale of the lifetimes of these objects, contradicting an assumption often made in the modelling of the flaring activity commonly observed in magnetars. Our work suggests that if a decaying magnetic field is indeed the cause of magnetar activity, the field evolution is likely to take place outside of the core, and might represent Hall/Ohmic diffusion in the stellar crust, or else that a mechanism other than standard ambipolar diffusion is active, e.g. flux expulsion due to the interaction between neutron vortices and magnetic fluxtubes.
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| 4. |
- Glampedakis, Kostas, et al.
(författare)
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Magnetohydrodynamics of superfluid and superconducting neutron star cores
- 2011
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Ingår i: Monthly notices of the Royal Astronomical Society. - : Royal Astronomical Society. - 0035-8711 .- 1365-2966. ; 410:2, s. 805-829
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Tidskriftsartikel (refereegranskat)abstract
- Mature neutron stars are cold enough to contain a number of superfluid and superconducting components. These systems are distinguished by the presence of additional dynamical degrees of freedom associated with superfluidity. In order to consider models with mixtures of condensates, we need to develop a multifluid description that accounts for the presence of rotational neutron vortices and magnetic proton fluxtubes. We also need to model the forces that impede the motion of vortices and fluxtubes, and understand how these forces act on the condensates. This paper concerns the development of such a model for the outer core of a neutron star, where superfluid neutrons co-exist with a type II proton superconductor and an electron gas. We discuss the hydrodynamics of this system, focusing on the role of the entrainment effect, the magnetic field, the vortex/fluxtube tension and the dissipative mutual friction forces. Our final results can be directly applied to a number of interesting astrophysical scenarios, e.g. associated with neutron star oscillations or the evolution of the large-scale magnetic field.
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| 5. |
- Lindström, Niclas, 1974-
(författare)
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Den nya syntesen och etik i undervisningen
- 2018
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Ingår i: Nordidactica. - Karlstad : CSD Karlstad. - 2000-9879. ; :2018:3, s. 27-43
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Tidskriftsartikel (refereegranskat)abstract
- Researchers within the educational field usually acknowledge the idea that teaching is an essentially moral activity. Yet, they seem to have different opinions on how teachers are supposed to complete that task in their everyday pedagogical practice. Jonathan Haidt has conducted a series of international studies, during recent years, revealing how people in general tend to respond ethically to situations that evoke strong emotional reactions. Based on the results he has presented a theory, the New Syntheses, in which he claims to explain the difference between the dominating moral pedagogical models and develop new approaches to teaching ethics. The present paper is based on a survey of Swedish teacher students and religious education teachers for which we have borrowed two of Jonathan Haidts examples. We discuss the New Synthesis in relation to the results of the surveys and the ethical dimension of the teaching profession. We argue that these results indicate a need for teacher students and teachers to consciously reflect on their values and methods for approaching ethics in education.
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| 6. |
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| 7. |
- Lindström, Niclas, 1974-, et al.
(författare)
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Lärares yrkesetik och etiskt resonerande
- 2018. - 1
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Ingår i: Läraren och yrkesetiken. - Lund : Studentlitteratur AB. - 9789144120881 ; , s. 59-81
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- En uppsättning yrkesetiska principer sätter ramar och ger riktlinjer för lärares verksamhet, men ofta är sådana principer i sig själva inte tillräckliga för att ge den vägledning som krävs för att lösa konkreta etiska problem. För det krävs också att läraren besitter färdigheter relevanta för att hantera etiska frågor, i synnerhet en förmåga till etiskt resonerande.
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| 8. |
- Lindström, Niclas, 1974-, et al.
(författare)
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Moral Taste and Moral Education : An Interview Study
- 2021
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Ingår i: Abstract Book 23rd Annual International Conference on Education. - Aten : Athens Institute for Education and Research (ATINER). - 9789605984021 ; , s. 46-
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Konferensbidrag (refereegranskat)abstract
- In recent research on moral psychology, the human consciousness has been compared to a tongue, with different taste buds, which together can cause a variety of sensations. According to this theory people, in general, have a preparedness to react to situations, which can provide opportunities or pose threats in a social context. Moral psychologist, Jonathan Haidt (2012, 2013), has described these receptors as pairs, for example: care/harm, justice/cheating, loyalty/betrayal, authority/subversion, holiness/degradation, and liberty/oppression. Which of these foundations the individual develops a taste for depends, largely, on the social and cultural context (Graham, Haidt & RimmKaufman 2008). Hence, the choices teachers make of which issues to address and in what way can contribute to a learning environment that influences their pupils‘ moral outlook. The purpose of this study is to investigate which of these moral intuitions or taste preferences that teachers want to endorse and cultivate in their pedagogical practices. Against this background, a number of qualitative research interviews were conducted with experienced teachers in the non-confessional subject religious education (RE), who have a particular responsibility for moral education in the Swedish school system. The interviews were partly based on a modified version of the Moral Foundations Questionnaire, which was deliberately developed in order to determine the participants‘ moral taste, and the participants were asked to elaborate their answers (Graham, Haidt & Nosek, 2008). The results of our study indicate that the participants tended to favour care and justice over loyalty, authority and holiness. As one of the participants puts it: "many of my examples relate to the weak and vulnerable or the ones that are denied their rights in society… these pedagogical choices are based on the content of the curriculum but also mirror my own preferences". In this paper we will analyze the interviews with the RE teachers and critically discuss the consequences the moral foundations theory have for moral education.
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| 9. |
- Lindström, Niclas, docent, 1974-, et al.
(författare)
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Moral Taste and Moral Education : An Interview Study
- 2022
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Ingår i: Athens Journal of Education. - Aten : Athens Institute for Education and Research (ATINER). - 2407-9898 .- 2241-7958. ; 9:3, s. 365-376
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Tidskriftsartikel (refereegranskat)abstract
- In recent research on moral psychology, the human consciousness has been compared to a tongue, with different taste buds, which together can cause a variety of sensations. According to this theory, people in general have a preparedness to react to situations, which can provide opportunities or pose threats in a social context. Moral psychologist, Jonathan Haidt, has described these receptors as pairs, for example: care/harm, fairness/cheating, loyalty/betrayal, authority/subversion and sanctity/degradation. Which of these foundations the individual develops a taste for depends, largely, on the social and cultural context. Hence, the choices teachers make of which issues to address and in what way can contribute to a learning environment that influences their pupils’ moral outlook. The purpose of this study is to investigate which of these moral intuitions or taste preferences that teachers want to endorse and cultivate in their pedagogical practices. Against this background, a number of qualitative research interviews were conducted with experienced teachers in the non-confessional subject religious education (RE), who have a particular responsibility for moral education in the Swedish school system. The interviews were based on a modified version of the Moral Foundations Questionnaire, which was deliberately developed to determine the participants’ moral taste, and the participants were asked to elaborate their answers. The results indicate that the participants tended to favour harm and fairness over loyalty, authority and sanctity. As one of the participants puts it: “many of my examples relate to the weak and vulnerable or the ones that are denied their rights in society… these pedagogical choices are based on the content of the curriculum but also mirror my own preferences”. In this paper we analyse the interviews with the RE teachers and critically discuss the consequences the moral foundations theory has for moral education.
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| 10. |
- Lindström, Niclas, 1974-, et al.
(författare)
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On how RE Teachers Address the Sometimes-Conflicting Tasks of Conveying Basic Values and Tools for Critical Thinking
- 2020
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Ingår i: Abstract Book. - Athens : Athens Institute for Education and Research (ATINER). - 9789605983253 ; , s. 41-41
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Konferensbidrag (refereegranskat)abstract
- A recurring idea, among practitioners and researchers, is that “teaching is a moral endeavour” where any act can convey “moral meaning” and “influence students” (Hansen, 2001, 826; Bulloughs, 2010; Campbell, 2013). Some have even stated that “all that can be seen and heard in classrooms” can be of moral significance, including “events, actions and even aspects of the physical environment” (Jackson, Boostrom & Hansen, 1998). Yet, they seem to be divided on how teachers ought to treat ideals, norms and values in their pedagogical practices.Hence, a division is often made between character-based and reason-based approaches to moral or ethics education. The difference can, somewhat simplified, be described schematically by their respective emphasis on group or individual, emotion or reason, habituation or critical assessment of universal ethical principles (for a more elaborated account see: Kohlberg, 1966, 2; Carr, 1983, 39; Graham, Haidt & Rimm-Kaufman, 2008, 271, 275). Even if the approaches are often described as mutually exclusive alternatives teachers are, nevertheless, often expected to perform these tasks in their everyday practices (see SNAE 2011).Against this background, we have conducted qualitative research interviews, with religious education (RE) teachers, who are considered to have a particular responsibility for moral and ethics education in the Swedish school system (Almén, 2000; Hartman, 2008; Larsson, 2009; Franck & Löfstedt, 2015). Our overall aim of this paper is to investigate how they relate to the sometimes conflicting responsibilities to convey a set of basic values and contribute to the pupils’ abilities to critically examine ideals, norms and values. Our analysis of the results shows that RE teachers use different strategies to describe and motivate their pedagogical choices (Yin, 1994; Bryman, 2008). We will, for instance, distinguish between a casuist-, a rights-, and an existentialist oriented approach to moral and ethics education and perform a critical discussion of the results.
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