Sökning: "Fysik och astronomi med inriktning mot teoretisk fysik"
Visar resultat 1 - 5 av 8 avhandlingar innehållade orden Fysik och astronomi med inriktning mot teoretisk fysik.
1. The Electronic Structure of Organic Molecular Materials : Theoretical and Spectroscopic Investigations
Sammanfattning : In the present thesis the electronic properties of two organic molecules were studied by means of density functional theory (DFT) in connection to their possible applications in organic photovoltaics and molecular spintronics respectively.The first analysed system is the C60 derivative PCBM extensively used in polymer solar cells for the charge separation process. LÄS MER
2. Atomic Processes in Stellar Atmospheres : Inelastic Collisions and Effects on Late-type Spectra
Sammanfattning : Chemical abundances as measured from stellar spectral lines are often subject to uncertainties due to lack of accurate data for inelastic collisions, which is needed for non-local thermodynamic equilibrium (non-LTE) modelling. For cool stars, understanding of collision processes with electrons and hydrogen atoms is required to achieve high precision measurements. LÄS MER
3. An Exploration of Q-Systems : From Spin Chains to Low-Dimensional AdS/CFT
Sammanfattning : The discovery of integrability in the planar limit of the AdS5/CFT4 correspondence has led to impressive progress in the study of string theory and four-dimensional N=4 Super-Yang-Mills. In particular, with the formulation of the Quantum Spectral Curve (QSC) the spectral problem is now solved. LÄS MER
4. Scattering Amplitudes in Supersymmetric Quantum Chromodynamics and Gravity
Sammanfattning : Quantum field theory is a theoretical framework for the description of nature in terms of fundamental particles, fields and their interactions. In the quantum regime, elementary scattering processes are observables in many experiments and studied in theoretical physics. LÄS MER
5. Bending, Twisting and Turning : Protein Modeling and Visualization from a Gauge-Invariance Viewpoint
Sammanfattning : Proteins in nature fold to one dominant native structure. Despite being a heavily studied field, predicting the native structure from the amino acid sequence and modeling the folding process can still be considered unsolved problems. In this thesis I present a new approach to this problem with methods borrowed from theoretical physics. LÄS MER