Sökning: "a theory of fields"

Visar resultat 6 - 10 av 640 avhandlingar innehållade orden a theory of fields.

1. 6. Dualities, Symmetries and Unbroken Phases in String Theory : Probing the Composite Nature of the String

   Författare :Johan Engquist; Joseph Minahan; Charlotte Kristjansen; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Theoretical Physics; String Theory; M-Theory; Higher Spin Gauge Theory; Super Yang-Mills Theory; Anti-de Sitter Spacetime; Singletons; Massless Higher Spin Gauge Fields; AdS CFT Correspondence; Spin Chains; Semiclassical Strings; Tensionless Limits; Conformal Symmetry; Supersymmetry; Higher Spin Gauge Symmetry; Integrability; Fysik; Physics; Fysik;

   Sammanfattning : The thesis treats aspects of string/M-theory in anti-de Sitter spacetimes and their supersymmetric completions. By applying the AdS/CFT correspondence, as well as models of spin chains and singletons, we try to attain a better understanding of the underlying symmetries and the unbroken phases of string/M-theory. LÄS MER

3. 7. Considering landscape in practices of transport planning

   Författare :Sofia Löfgren; Charlotta Johansson; Kristina L. Nilsson; Simin Davoudi; Luleå tekniska universitet; []
   Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; transport planning; knowledge; landscape; planning theory; Architecture; Arkitektur;

   Sammanfattning : A well-known challenge in planning is for the professionals involved to handle multiple sources ofknowledge and to influence decision-making as a result. This challenge is the main focus of this research and in order to explore it I have directed attention to the integration of knowledge pertaining to landscape in practices of transport planning. LÄS MER

4. 8. Exploring effective descriptions of gauge fields and strings : A Lagrangian approach with insights from color-kinematics duality

   Författare :Lucia M. Garozzo; Henrik Johansson; Chris White; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; scattering amplitudes; double copy; gauge theory; string theory; Theoretical Physics; Teoretisk fysik;

   Sammanfattning : The concept of a color-kinematics duality is an important driving force in advancing the modern understanding of scattering amplitudes, in both field theory and string theory. Yet, open questions remain that motivate the need for a deeper understanding of the duality. LÄS MER

5. 9. The effect of nano-confinement on hydrogen uptake in metallic superlattices

   Författare :Sotirios A. Droulias; Max Wolff; Gunnar K. Pálsson; Björgvin Hjörvarsson; Daniel Azofeifa; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : The absorption of hydrogen is exothermic in vanadium whereas it is endothermic in iron and chromium. Investigations of the hydrogen uptake within Fe/V(001) and Cr/V(001) superlattices allow therefore a detailed exploration of finite size effects and the influence of boundaries on hydrogen absorption. LÄS MER

7. 10. Phase-field modeling of stress-induced precipitation and kinetics in engineering metals

   Författare :Claudio F. Nigro; Christina Bjerkén; Ylva Mellbin; Pär A T Olsson; Reinhart Pippan; Malmö universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; phase-field theory; finite element method; corrosion; finite volume method; phase transformation; hydride; hydrogen embrittlement; linear elastic fracture mechanics;

   Sammanfattning : The formation of brittle compounds in metals operating in corrosive environments can be a tremendous source of embrittlement for industrial structures and such phenomenon is commonly enhanced in presence of stresses. To study this type of microstructural change modeling is preferred to experiment to reduce costs and prevent undesirable environmental impacts. LÄS MER