Spelling suggestions: "subject:"On dilling"" "subject:"On 4illing""
1 |
The existence and structure of constants of geodesic motion admitted by spherically symmetric static space-timesHowarth, Laura January 1999 (has links)
No description available.
|
2 |
Spinorial characterisations of rotating black hole spacetimesCole, Michael January 2018 (has links)
In this thesis, the implications of the existence of Killing spinors in a spacetime are investigated. In particular, it is shown that in vacuum and electrovacuum spacetimes a Killing spinor, along with some assumptions on the associated Killing vector in an asymptotic region, guarantees that the spacetime is locally isometric to a member of the Kerr or Kerr-Newman family. It is shown that the characterisation of these spacetimes in terms of Killing spinors is an alternative expression of characterisation results of Mars (Kerr) and Wong (Kerr-Newman) involving restrictions on the Weyl curvature and matter content. In the next section, the construction of a geometric invariant characterising initial data for the Kerr-Newman spacetime is described. This geometric invariant vanishes if and only if the initial data set corresponds to exact Kerr-Newman initial data, and so characterises this type of data. First, the characterisation of the Kerr-Newman spacetime in terms of Killing spinors is illustrated. The space spinor formalism is then used to obtain a set of four independent conditions on an initial Cauchy hypersurface that guarantee the existence of a Killing spinor on the development of the initial data. Following a similar analysis in the vacuum case, the properties of solutions to the approximate Killing spinor equation are studied, and used to construct the geometric invariant. Finally, the problem of Killing spinor initial data in the characteristic problem is investigated. It is shown that data need only be speci ed on the bifurcation surface of the two intersecting null hypersurfaces in order to guarantee the existence of a Killing spinor in a neighbourhood of the bifurcation surface. This characterises the class of spacetimes known as distorted black holes, which include but is strictly larger than the Kerr family of spacetimes.
|
3 |
Campos de Killing, curvatura média e translaçõesPeixoto, Cíntia Rodrigues de Araújo January 2005 (has links)
D. Hoffman, R. Osserman e R. Schoen mostraram que se a aplicação de Gauss de uma superfície orientada completa de curvatura média constante M imersa em R³ está contida em um hemisfério fechado de S² (equivalentemente, a função <n, V> não muda de sinal em M, onde n é um vetor unitário normal de M e v algum vetor não nulo de R³), então M é invariante por um subgrupo a um parâmetro de translações de R³ (aquele determinado por v). Neste trabalho obtemos uma extensão deste resultado para o caso em que o espaço ambiente é uma variedade riemanniana e M uma hipersuperfície em N requerendo que a função <n, V> não mude de sinal em M, onde V é um campo de Killing em N. Na parte final deste trabalho consideramos uma variedade riemanniana Killing paralelizável N para definir uma translação Y: M -> Rn de uma hipersuperfície M de N que é uma extensão natural da aplicação de Gauss de uma hipersuperfície de Rn. Considerando as mesmas hipóteses para a imagem de y obtemos uma extensão do resultado original de Hoffman-Osserman-Schoen. / D. Hoffman, R. Osserman and R. Schoen proved that if the Gauss map of a complete constant mean curvature oriented surface M immersed in R³ is contained in a closed hemisphere of S² (equivalently, the function <n, V> does not change sign on M where n is a unit normal vector of M and v some non zero vector of R³), then M is invariant by a one parameter subgroup of translations of R³ (the one determined by v). In this work we obtain an extension of this result to the case that the ambient space is a Riemannian manifold and M a hypersurface on N by requiring that the function <n, V> does not change sign on M, where V is a Killing field on N. In the last part of this work we consider a Killing paralelizable Riemannian manifold N to define a translation map y : M -> Rn of a hypersurface M of N which is a natural extension of the Gauss map of a hypersurface in Rn. Considering the same hypothesis on the image of y we obtain, an extension to this setting, of the original Hoffman-Osserman-Schoen result.
|
4 |
Campos de Killing, curvatura média e translaçõesPeixoto, Cíntia Rodrigues de Araújo January 2005 (has links)
D. Hoffman, R. Osserman e R. Schoen mostraram que se a aplicação de Gauss de uma superfície orientada completa de curvatura média constante M imersa em R³ está contida em um hemisfério fechado de S² (equivalentemente, a função <n, V> não muda de sinal em M, onde n é um vetor unitário normal de M e v algum vetor não nulo de R³), então M é invariante por um subgrupo a um parâmetro de translações de R³ (aquele determinado por v). Neste trabalho obtemos uma extensão deste resultado para o caso em que o espaço ambiente é uma variedade riemanniana e M uma hipersuperfície em N requerendo que a função <n, V> não mude de sinal em M, onde V é um campo de Killing em N. Na parte final deste trabalho consideramos uma variedade riemanniana Killing paralelizável N para definir uma translação Y: M -> Rn de uma hipersuperfície M de N que é uma extensão natural da aplicação de Gauss de uma hipersuperfície de Rn. Considerando as mesmas hipóteses para a imagem de y obtemos uma extensão do resultado original de Hoffman-Osserman-Schoen. / D. Hoffman, R. Osserman and R. Schoen proved that if the Gauss map of a complete constant mean curvature oriented surface M immersed in R³ is contained in a closed hemisphere of S² (equivalently, the function <n, V> does not change sign on M where n is a unit normal vector of M and v some non zero vector of R³), then M is invariant by a one parameter subgroup of translations of R³ (the one determined by v). In this work we obtain an extension of this result to the case that the ambient space is a Riemannian manifold and M a hypersurface on N by requiring that the function <n, V> does not change sign on M, where V is a Killing field on N. In the last part of this work we consider a Killing paralelizable Riemannian manifold N to define a translation map y : M -> Rn of a hypersurface M of N which is a natural extension of the Gauss map of a hypersurface in Rn. Considering the same hypothesis on the image of y we obtain, an extension to this setting, of the original Hoffman-Osserman-Schoen result.
|
5 |
Campos de Killing, curvatura média e translaçõesPeixoto, Cíntia Rodrigues de Araújo January 2005 (has links)
D. Hoffman, R. Osserman e R. Schoen mostraram que se a aplicação de Gauss de uma superfície orientada completa de curvatura média constante M imersa em R³ está contida em um hemisfério fechado de S² (equivalentemente, a função <n, V> não muda de sinal em M, onde n é um vetor unitário normal de M e v algum vetor não nulo de R³), então M é invariante por um subgrupo a um parâmetro de translações de R³ (aquele determinado por v). Neste trabalho obtemos uma extensão deste resultado para o caso em que o espaço ambiente é uma variedade riemanniana e M uma hipersuperfície em N requerendo que a função <n, V> não mude de sinal em M, onde V é um campo de Killing em N. Na parte final deste trabalho consideramos uma variedade riemanniana Killing paralelizável N para definir uma translação Y: M -> Rn de uma hipersuperfície M de N que é uma extensão natural da aplicação de Gauss de uma hipersuperfície de Rn. Considerando as mesmas hipóteses para a imagem de y obtemos uma extensão do resultado original de Hoffman-Osserman-Schoen. / D. Hoffman, R. Osserman and R. Schoen proved that if the Gauss map of a complete constant mean curvature oriented surface M immersed in R³ is contained in a closed hemisphere of S² (equivalently, the function <n, V> does not change sign on M where n is a unit normal vector of M and v some non zero vector of R³), then M is invariant by a one parameter subgroup of translations of R³ (the one determined by v). In this work we obtain an extension of this result to the case that the ambient space is a Riemannian manifold and M a hypersurface on N by requiring that the function <n, V> does not change sign on M, where V is a Killing field on N. In the last part of this work we consider a Killing paralelizable Riemannian manifold N to define a translation map y : M -> Rn of a hypersurface M of N which is a natural extension of the Gauss map of a hypersurface in Rn. Considering the same hypothesis on the image of y we obtain, an extension to this setting, of the original Hoffman-Osserman-Schoen result.
|
6 |
History in the literary imagination : the telling of Nongqawuse and the Xhosa cattle-killing in South African literature and culture (1891-1937)Boniface Davies, Sheila January 2011 (has links)
This thesis takes as its subject the millenarian movement of 1856-7, commonly known as the Xhosa Cattle-Killing. My project examines a range of literary representations of this seminal moment in South African history: novels, plays, and short stories in English or English translation. The period under consideration encompasses the earliest literary responses to the Cattle-Killing and includes critical historical-political moments such as: the incorporation of the last independent black territory into the Cape Colony, the creation of the Union of South Africa, the passing of the Land Act, the enfranchisement of white women and the enactment of Hertzog's 'native bills'. The project consists of close, contextual readings, and the approach is cross-cultural and interdisciplinary. In this dissertation I examine the meaning that has accrued to the Cattle-Killing, and the role that literary accounts have played in interpreting and defining this pivotal event in the historical consciousness of their sometimes considerable audiences. In some cases, these creative works have anticipated trends in formal historiography and suggested new ways to interrogate the evidence. But the accounts do more than creatively reconstruct the past. They are also implicated in their respective presents and use the Cattle-Killing to 'write out' contemporaneous concerns: be it female emancipation, 'native education' or Black Nationalism. The various manifestations of the Cattle-Killing story chart not only the shifting 'truth' of the event but also the ways in which it has been made relevant and useable for different communities at various points in South Africa's history. To read these accounts of the Cattle-Killing, I argue, is to 'read' the history of this period. While taking as its subject an event from 150 years ago, and literary responses from shortly after, my project contributes to wider, on-going conversations relating to history as a field of argument and literature as a social and historical force. A related aim is to contribute to the revaluation of early South African literature, which has been neglected or homogenized in recent years. My dissertation seeks to recuperate and complicate by representing a variety of subject positions and resuscitating voices discarded or forgotten.
|
7 |
Mannens heder är livet, kvinnans vanheder är döden : Förövarnas legitimering av hedersmordWilén, Beian January 2016 (has links)
Mannens heder är livet, kvinnans vanheder är döden Förövarnas legitimering av hedersmord Beian Wilén Den största rädslan i en hederskultur är risken att förlora sin heder och då även sin sociala status. För kvinnorna gäller det att bevara sin kyskhet och att följa de sociala koderna oavsett om hon blir förtryckt och kontrollerad. När en kvinna blir misstänkliggjord och rykten börjar florera tvingas mannen agera för att rena skammen, och enda lösningen är hedersmord. I denna innehållsanalys användes nio hedersrelaterade domar där 11 gärningsmän dömdes för mord. Syftet med detta var att ta reda på hur gärningsmännen legitimerar sitt brott i relation till hedersbegreppet. Resultatet påvisade fyra centrala kategorier som gärningsmännen använde för att legitimera sitt brott (1) kränkta och vanhedrade, (2) oro och psykisk instabilitet, (3) nödvärn, (4) förnekelse av heder. Framtida forskning kan leda till att utveckla metoder som kan användas i samtal med ungdomar som lever i en hederskultur för att påverka deras sätt att tänka kring heder. Keywords: honor, dishonor, culture, violence, honor killing
|
8 |
Förberedelser inför den väpnade striden : Två verktyg; Idrottspsykologi och samtal om döden / Preparations for the armed battle : Two tools; Physiological psychology and discussion about deathSpetz, David January 2009 (has links)
<p>The combat mission is an extreme situation with high demands of the soldier. Killing might very well be necessary. Before a mission a soldier can experience stress due to these factors. The purpose of this paper is to find methods to handle stress due to an upcoming combat mission and to the prospect of having to kill. The main questions of this essay: -<em>How can certain parts of the physiological psychology improve a soldiers ability to perform a mission?</em> <em>– Is the Swedish soldier mentally prepared to kill?</em> The theory for this essay has been described using litteratur by experts within the field, and the results thereafter discussed. The results: Technics such as objective planning, routines, visualisation and discussions about killing has a positive effect on the soldier’s stress level. It prevents stress and improves his ability during the mission. Future battle planners should integrate this into training before a mission.</p>
|
9 |
Förberedelser inför den väpnade striden : Två verktyg; Idrottspsykologi och samtal om döden / Preparations for the armed battle : Two tools; Physiological psychology and discussion about deathSpetz, David January 2009 (has links)
The combat mission is an extreme situation with high demands of the soldier. Killing might very well be necessary. Before a mission a soldier can experience stress due to these factors. The purpose of this paper is to find methods to handle stress due to an upcoming combat mission and to the prospect of having to kill. The main questions of this essay: -How can certain parts of the physiological psychology improve a soldiers ability to perform a mission? – Is the Swedish soldier mentally prepared to kill? The theory for this essay has been described using litteratur by experts within the field, and the results thereafter discussed. The results: Technics such as objective planning, routines, visualisation and discussions about killing has a positive effect on the soldier’s stress level. It prevents stress and improves his ability during the mission. Future battle planners should integrate this into training before a mission.
|
10 |
(O)avsiktliga följder av vindkraft : - en tolkning av villkoret "avsiktligt" i artskyddsförordningenLundmark, Linn January 2015 (has links)
Wind turbines are a cleaner alternative to non-renewable energy, such as fossil fuels, and therefore help to decrease deleterious climate change.[1] Species protection is needed to preserve biodiversity, which is important to all species.[2] It is claimed, however, that between these interests there is a contradiction. Climate change kills birds, but so do wind turbines. According to some, the expansion of wind power is at risk, being hindered by the rules on protected birds, incorrectly interpreted in artskyddsförordningen[3], the Swedish counterpart to international species conventions and the EU Birds directive[4].[5] The Birds directive and artskyddsförordningen prohibits activities that deliberately kill, capture or disturb migratory birds in the EU (art. 5 Birds directive and 4 § artskyddsförordningen). Mark- och miljööverdomstolen has for some years made the assessment that the establishment and operation of wind turbines may be prohibited by reason of the protection of species, even though the purpose of wind power is to produce electricity and not to kill birds.[6] Due to the legal uncertainty, this essay seeks to find out whether wind energy can fall within artskyddsförordningens prohibitions and if so, when. This is done through a legal dogmatic method, complemented with a comparative section. The legal situation is not clear, but after a thorough examination of the origin of the Birds directive, previous case law, new disputed ruling by Mark- och miljööverdomstolen, Danish and German case law, ECJ rulings and guidance documents from the European Commission, in total it seems that an inappropriate placement of wind farms or plants can and sometimes should be seen as a deliberate act in respect of the Birds directive and consequently artskyddsförordningen. That is, unless it is possible to undertake precautionary measures, which neutralizes the act. It also appears that artskyddsförordningen still is to be applied within chapter 2 miljöbalken[7], in the case of species protection. [1] SOU 1999:75, s. 29 f. [2] SOU 2004:37, s. 189. [3] Artskyddsförordningen (2007:845). [4] Directive 2009/147/EC of the European parliament and of the council of 30 November 2009 on the conservation of wild birds. [5] Mark- och miljööverdomstolen har klargjort att vindkraft inte innebär ett avsiktligt dödande eller störande enligt artskyddsförordningen – kommentar av Magnus Fröberg och Hedvig Ekdahl, 2015-01-23, JP Infonet. [6] Se exempelvis MÖD 2013:13. [7] Miljöbalken (1998:808).
|
Page generated in 0.0698 seconds