[en] This book provides a postgraduate level introduction to gauge field theory entirely from a path integral standpoint without any reliance on the more traditional method of canonical quantisation. The ideas are developed by quantising the self-interacting scalar field theory, and are then used to deal with all the gauge field theories relevant to particle physics, quantum electrodynamics, quantum chromodynamics, electroweak theory, grand unified theories, and field theories at non-zero temperature. The use of these theories to make precise experimental predictions requires the development of the renormalised theories. This book provides a knowledge of relativistic quantum mechanics, but not of quantum field theory. The topics covered form a foundation for a knowledge of modern relativistic quantum field theory, providing a comprehensive coverage with emphasis on the details of actual calculations rather than the phenomenology of the applications

No abstract available

[en] We construct intersecting D5-brane orbifold models that yield the (non-supersymmetric) standard model up to vector-like matter and charged-singlet scalars. The models are constrained by the requirement that twisted tadpoles cancel, and that the gauge boson coupled to the weak hypercharge U(1)_Y does not get a string-scale mass via a generalised Green-Schwarz mechanism. Gauge coupling constant ratios close to those measured are easily obtained for reasonable values of the parameters, consistently with having the string scale close to the electroweak scale, as required to avoid the hierarchy problem

[en] We construct a new set of intersecting D4-brane models that yield the (non-supersymmetric) standard model up to vector-like matter and, in some cases, extra U(1) factors in the gauge group. The models are constrained by the requirement that twisted tadpoles cancel, and that the gauge boson coupled to the weak hypercharge U(1)_Y does not get a string-scale mass via a generalised Green-Schwarz mechanism. We find six-stack models that contain all of the Yukawa couplings to the tachyonic Higgs doublets that are needed to generate mass terms for the fermions at renormalisable level, but which have charged-singlet scalar tachyons and an unwanted extra U(1) gauge symmetry after spontaneous symmetry breaking. There is also a six-stack model without any unwanted gauged U(1) symmetries, but which only has the Yukawa couplings to generate masses for the u quarks and charged leptons. A particular eight-stack model is free of charged-singlet tachyons and has gauge coupling strengths whose ratios at the string scale are close to those measured at the electroweak scale, consistent with the string scale being at most a few TeV

No abstract available

[en] Exposure reconstructions for radionuclides are inherently difficult. As a result, most reconstructions are based primarily on mathematical models of environmental fate and transport. These models can have large uncertainties, as important site-specific information is unknown, missing, or crudely estimated. Alternatively, surrogate environmental measurements of exposure can be used for site-specific reconstructions. In cases where environmental transport processes are complex, well-chosen environmental surrogates can have smaller exposure uncertainty than mathematical models. Because existing methodologies have significant limitations, the development or improvement of methodologies for reconstructing exposure from environmental measurements would provide important additional tools in assessing the health effects of chronic exposure. As an example, the direct measurement of tritium atoms by accelerator mass spectrometry (AMS) enables rapid low-activity tritium measurements from milligram-sized samples, which permit greater ease of sample collection, faster throughput, and increased spatial and/or temporal resolution. Tritium AMS was previously demonstrated for a tree growing on known levels of tritiated water and for trees exposed to atmospheric releases of tritiated water vapor. In these analyses, tritium levels were measured from milligram-sized samples with sample preparation times of a few days. Hundreds of samples were analyzed within a few months of sample collection and resulted in the reconstruction of spatial and temporal exposure from tritium releases

[en] Renormalisation group equations are derived from the Ginzburg-Landau free energy for p-wave paired neutron-star matter in the presence of large magnetic fields. The effect of fluctuations on the nature of the superfluid phase transition is discussed. (author)

[en] Singular and non-singular textures of the planar phase of superfluid ³He are classified using topological homotopy group methods. The effects of an applied magnetic field and of boundary conditions at the walls of the container are discussed. (author)

[en] The BCS free energy for ₃P² paired neutron matter is derived taking account of relativistic effects. It is found that the values taken by the Ginzburg-Landau parameters are always in the region of the phase diagram corresponding to a unitary phase. (author)

No abstract available