Inclusion of Diffraction Effects in the Gutzwiller Trace Formula

The Gutzwiller trace formula is extended to include diffraction effects. The new trace formula involves periodic rays which have non-geometrical segments as a result of diffraction on the surfaces and edges of the scatter.Comment: 4 pages, LaTeX, 1 ps figur

Application of the diffraction trace formula to the three disk scattering system

The diffraction trace formula ({\em Phys. Rev. Lett.} {\bf 73}, 2304 (1994)) and spectral determinant are tested on the open three disk scattering system. The system contains a generic and exponentially growing number of diffraction periodic orbits. In spite of this it is shown that even the scattering resonances with large imaginary part can be reproduced semiclassicaly. The non-trivial interplay of the diffraction periodic orbits with the usual geometrical orbits produces the fine structure of the complicated spectrum of scattering resonances, which are beyond the resolution of the conventional periodic orbit theory.Comment: Latex article + 3 ps figure

Dental utilisation by young adults before and after subsidisation reform in Finland

Dental care was never fully integrated into the welfare state in Finland, but in 1986 it was decided to improve access to both publicly and privately provided dental care by reducing the price paid by patients. Since this would have been rather expensive to do for the whole population, it was decided to introduce it gradually, starting with the young adult population (those under 21 already had free publicly provided dental care). The so-called “Subsidisation Reform” (SR) was based on the assumption that the seeking of care would increase, as would the amount of care actually provided, and this increase would be spread across both the public and the private sectors. This study investigates the short-term effects of this reform. The seeking of care did increase, but the amount of care actually provided decreased and the changes were not evenly spread between the two sectors. The reasons for these changes are explored, and some of the inherent difficulties in evaluating health care reforms are set out, since they are likely to be of wider significance than this particular reform in Finland.reform, dental care

Replik till Lisa Furberg: ‘Feminism, perfektionism och surrogatmoderskap’

Lisa Furberg har argumenterat för att altruistiskt surrogatmödraskap kan anses moraliskt problematiskt utifrån en perfektionistisk teori om det goda livet. I följande svar riktar jag ett antal invändningar mot Furbergs resonemang

Oorganiserade kollektiv kan handla

Jag argumenterar för att oorganiserade kollektiv, såsom kollektivet av alla människor, kan handla moraliskt rätt och fel. Storskaliga problem likt den globala uppvärmningen är till exempel resultatet av en sådan kollektiv handling, nämligen hela mänsklighetens utsläpp av växthusgaser. Denna kollektiva handling är dessutom moraliskt fel, på grund av dess dåliga konsekvenser. Jag bemöter också en invändning mot denna uppfattning om kollektivt handlande, enligt vilken det är intuitivt orimligt att oorganiserade kollektiv såsom ”hela mänskligheten” kan handla

Varför Tännsjö bör bli vegetarian

Jag argumenterar för att Torbjörn Tännsjö borde anse det fel att äta kött. Därför borde han bli vegetarian. Anledningen till detta är en artikel, "Why we ought to accept the repugnant conclusion", som Tännsjö publicerade 2002 i tidskriften Utilitas

Coherentism and the Sensation Objection

Coherentist theories of justification face the Sensation objection, according to which some experiences, such as that of a headache, independently justify us in holding certain beliefs regardless of whether they cohere with the rest of our beliefs. Since coherentism holds that our beliefs are justified only on the basis of coherence with the rest of our beliefs, coherentism is, or so it has been argued, false. But the Sensation objection fails. First of all, there is no independent justification going on in these cases. And second, a variant of BonJour's theory of introspection can make sense of these cases within a pure coherentist position

Hedonistic Act Utilitarianism: Action Guidance and Moral intuitions

According to hedonistic act utilitarianism, an act is morally right if and only if, and because, it produces at least as much pleasure minus pain as any alternative act available to the agent. This dissertation gives a partial defense of utilitarianism against two types of objections: action guidance objections and intuitive objections. In Chapter 1, the main themes of the dissertation are introduced. The chapter also examines questions of how to understand utilitarianism, including (a) how to best formulate the moral explanatory claim of the theory, (b) how to best interpret the phrase "pleasure minus pain," and (c) how the theory is related to act consequentialism. The first part (Chapters 2 and 3) deals with action guidance objections to utilitarianism. Chapter 2 defines two kinds of action guidance: doxastic and evidential guidance. It is argued that utilitarianism is evidentially but not doxastically guiding for us. Chapter 3 evaluates various action guidance objections to utilitarianism. These are the objections that utilitarianism, because it is not doxastically guiding, is a bad moral theory, fails to be a moral theory, is an uninteresting and unimportant moral theory, and is a false moral theory. The second part (Chapters 4, 5 and 6) deals with intuitive objections to utilitarianism. Chapter 4 presents three intuitive objections: Experience Machine, Transplant, and Utility Monster. Three defenses of utilitarianism are subsequently evaluated. Chapter 5 and 6 introduces two alternative defenses of utilitarianism against intuitive objections, both of which concern the role that imagination plays in thought experimentation. In Chapter 5, it is argued that we sometimes unknowingly carry out the wrong thought experiment when we direct intuitive objections against utilitarianism. In many such cases, we elicit moral intuitions that we believe give us reason to reject utilitarianism, but that in fact do not. In Chapter 6, it is argued that using the right kind of sensory imagination when we perform thought experiments will positively affect the epistemic trustworthiness of our moral intuitions. Moreover, it is suggested that doing so renders utilitarianism more plausible. In Chapter 7, the contents of the dissertation are summarized

Assessing the Utility of Imaging Radar for Identifying White Sand Vegetation Structure

White sand vegetation communities are wide spread across South America; found in Peru, Venezuela, Brazilian Amazon and Guyana. They are distributed in patches ranging from \u3c1 km2 to greater than tens of square kilometers and their origins and locations are still not well understood. The communities are related to a variety of factors (soil type, flooding, nutrient content and fire); hence a precise definition for the ecosystem is still not fully defined. Nevertheless, the result of these variations creates a unique environment for endemic plant and animal species to thrive. Furthermore, analysis of these areas has been very scattered and identification of local white sand areas (\u3c1 km2) have not been accomplished. In addition, identification of these locations has currently only used optical satellite imagery (Landsat, MODIS). Hence, in this project, we have attempted to use synthetic aperture radar to create a classification system to locate the white sand vegetation systems. The goal is to be able to apply this method to identify white sand vegetation distribution across South America. The region of focus for this thesis has been in Aracá, a large white sand area located in Brazil in the State of Amazonas. Due to the lack of ground reference data, a classified map by Capurucho et al. (2013), generated using Landsat data, was used as a comparison and reference. JAXA’s ALOS-1 PALSAR (L-band), ESA’s Sentinel-1A (C-band) and NASA’s SRTM sensors were used for land classification. As microwave signals penetrate clouds and haze, the advantage of using sensors with this wavelength allows for an unobstructed coverage of the landscape all year round. Different combinations of polarizations and wavelengths were used during the analysis to try and separate the white sand vegetation from water and terra firme forest. The resulting classification images showed a 30% agreement with the classification map by Capurucho et al. It is important to note, that this number is in fact an agreement percentage as the map used was a classification image and coarse in resolution (due to the lack of reference data). Therefore, this value does not imply a bad classification. Future work will include time-series data, precise ground reference points and data from other sensors such as ALOS-2 PALSAR, to improve the classification accuracy