Sökning: "qft"

Visar resultat 1 - 5 av 16 uppsatser innehållade ordet qft.

1. 1. Cosmological Horizons and the Unruh Effect

   L3-uppsats, Uppsala universitet/Teoretisk fysik

   Författare :Niklas Engelhardt Önne; [2023]
   Nyckelord :Unruh effect; quantum scalar fields; Bogoliubov transformations; accelerated observers; Minkowski spacetime; cosmological horizons; Rindler observers; special relativity; QFT; Unruh-effekten; skalära kvantfält; Bogoliubov-transformationer; accelererande referenssystem; Minkowski rumtid; kosmologiska horisonter; Rindlerobservatörer; speciell relativitetsteori; QFT;

   Sammanfattning : The black hole information paradox, which states that the evaporation of black holes due to Hawking radiation results in a violation of the conservation of quantum information, is arguably one of the most fundamental problems in all of modern physics. Through the equivalence principle, the essence of the problem can be understood and studied in the context of much simpler flat spacetime (described by the theory of special relativity); in this context the Hawking radiation takes the form of the so-called Unruh effect, a thermal effect in the vacuum of a Minkowski quantum field theory that can be measured by accelerated observers. LÄS MER

3. 2. Path Integrals in Quantum Mechanics and Low-Dimensional QFT

   Kandidat-uppsats, Uppsala universitet/Teoretisk fysik

   Författare :Johanna Adbo; [2023]
   Nyckelord :QFT; path integrals; quantum mechanics; kvantfältteori; vägintegraler; kvantmekanik;

   Sammanfattning : The focus of this thesis is to introduce the path integral and some of its applications. One interpretation of quantum mechanics is that a microscopic system which moves from an initial- to a final state moves through each possible intermediate state. LÄS MER

4. 3. Pure Yang-Mills amplitudes in 5 Dimensions : A study of vector boson amplitudes at 4 and 5 points

   Master-uppsats, Uppsala universitet/Teoretisk fysik

   Författare :Athanasios Voutouras; [2023]
   Nyckelord :Yang-Mills; Scattering; Amplitudes; QFT;

   Sammanfattning : In this text we explore the case of pure Yang-Mills amplitudes in 5 spacetime dimensions for vector particles. Extending current toolsets such as the Spinor-Helicity formalism in 5D would be beneficial to the study of the various cases of super Yang-Mills and supergravity. LÄS MER

5. 4. Calculating scattering amplitudes in φ3 and Yang-mills theory using perturbiner methods

   L3-uppsats, Uppsala universitet/Teoretisk fysik

   Författare :Daniel Nilsson; Magnus Bertilsson; [2022]
   Nyckelord :QFT; Quantum; Quantum field theory; scattering amplitudes; Berends Giele Currents; feynman diagrams; n particle scattering;

   Sammanfattning : We calculate tree-level scattering amplitudes in φ^3 theory and Yang-Mills theory by means of the perturbiner expansion. This involves solving the Euler-Lagrange equations of motion perturbatively via a multi-particle ansatz, and using Berends-Giele recursion relations to extract the solution from simple on-shell data. LÄS MER

7. 5. The Swampland and Early Universe Cosmology

   Master-uppsats, Uppsala universitet/Teoretisk fysik

   Författare :Alexia Nix; [2022]
   Nyckelord :Swampland; Early Universe; String Theory; Cosmology; Effective Field Theory; Dark Energy.;

   Sammanfattning : Until now the quantum field theory (QFT) that successfully describes the electric, weak and strong interactions (three out of the four fundamental forces) between particles is the Standard Model, but it omits gravity. The prime candidate for a quantum theory of gravity is string theory. LÄS MER