Gravitational and gauge interactions

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What Caused the Big Bang?

This book critically explores answers to the big question, What produced our universe around fifteen billion years ago in a Big Bang? It critiques contemporary atheistic cosmologies, including Steady State, Oscillationism, Big Fizz, Big Divide, and Big Accident, that affirm the eternity and self-sufficiency of the universe without God. This study defends and revises Process Theology and arguments for God's existence from the universe's life-supporting order and contingent existence

Twisted and unstable : approaches to the string equations of motion

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2006.Includes bibliographical references (p. 183-197).In this thesis we will explore three approaches to aspects of the fundamental structure of string theory. We first provide a brief review of perturbative string theory, and briefly discuss how each of the three topics to be discussed in the body of this thesis depart from this starting point. We then study the open string one-loop tadpole diagram in Witten cubic open string field theory. We compute this diagram both analytically and numerically and study the divergences arising from the collective behavior of open string fields in the short-distance region of the diagram. We demonstrate that this region of the diagram encodes information about the linearized Einstein equation describing the shift in the closed string fields in reaction to the D-brane supporting the open strings. We also show that the manner in which this information is encoded is somewhat singular, and comment on the implications for the quantum consistency of open bosonic string field theory. We next compute the closed string radiation from a decaying D-brane in type II string theory. The calculation is made possible by noting that the integrals involved in the requisite disk one-point functions reduce to integrals over the group manifold of a product of unitary groups.(cont.) We find that the total number and energy of strings radiated during the decay process diverges for D-branes of small enough dimension, in precise analogy to the bosonic case. Finally, we investigate a simple class of type II string compactifications which incorporate nongeometric "fluxes" in addition to "geometric flux" and the usual H-field and R-R fluxes. We develop T-duality rules for NS-NS geometric and nongeometric fluxes, which we use to construct a superpotential for the dimensionally reduced four-dimensional theory. The resulting structure is invariant under T-duality, so that the distribution of vacua in the IIA and IIB theories is identical when nongeometric fluxes are included.by Jessie (Julia) Shelton.Ph.D

Loops, Knots, Gauge Theories

This volume provides a self-contained introduction to applications of loop representations, and the related topic of knot theory, in particle physics and quantum gravity. These topics are of considerable interest because they provide a unified arena for the study of the gauge invariant quantization of Yang-Mills theories and gravity, and suggest a promising approach to the eventual unification of the four fundamental forces. The book begins with a detailed review of loop representation theory and then describes loop representations in Maxwell theory, Yang-Mills theories as well as lattice techniques. Applications in quantum gravity are then discussed, with the following chapters considering knot theories, braid theories and extended loop representations in quantum gravity. A final chapter assesses the current status of the theory and points out possible directions for future research. First published in 1996, this title has been reissued as an Open Access publication

Exploring the Web of Heterotic String Theories using Anomalies

We investigate how anomalies can be used to infer relations among different descriptions of heterotic string theory. Starting from the observation that the construction mechanism of heterotic orbifold compactifications considered up to now prevents them from being resolved into fully smooth Calabi-Yau compactification manifolds, we use a new mechanism to obtain an orbifold which does not suffer from the aforementioned limitations. We explain in general how to resolve orbifolds into smooth Calabi-Yaus using toric geometry and gauged linear sigma models. The latter allow for studying the theory in various other regions of the string moduli space as well, which unveils interesting intermediate geometries. By following anomalies through the different regimes, we can match the orbifold theories to their smooth Calabi-Yau counterparts. In the process, we investigate discrete R and non-R orbifold symmetries and propose a mechanism for studying their fate in other regions of the moduli space. Finally, we introduce a novel anomaly cancelation mechanism in gauged linear sigma models, which manifests itself in target space as a description of compactification geometries with torsion and Neveu-Schwarz five branes

John Archibald Wheeler : a study of mentoring in modern physics

This dissertation has two objectives. The first objective is to determine where best to situate the study of mentoring (i.e. the 'making of scientists') on the landscape of the history of science and science studies. This task is accomplished by establishing mentoring studies as a link between the robust body of literature dealing with Research Schools and the emerging scholarship surrounding the development, dispersion, and evolution of pedagogy in the training of twentieth century physicists. The second, and perhaps more significant and novel objective, is to develop a means to quantitatively assess the mentoring workmanship of scientific craftsmen who preside over the final stages of preparation when apprentices are transformed into professional scientists. The project builds upon a 2006 Master's Thesis that examined John Archibald Wheeler’s work as a mentor of theoretical physicists at Princeton University in the years 1938 - 1976. It includes Wheeler's work as a mentor at the University of Texas and is qualitatively and quantitatively enhanced by virtue of the author having access to five separate collections with archival holdings of John Wheeler's papers and correspondence, as well as having access to thirty one tape recorded interviews that feature John Wheeler as either the interviewee or a prominent subject of discussion. The project also benefited from the opportunity to meet with and gather background information from a number of John Wheeler's former colleagues and students. Included in the dissertation is a content analysis of the acknowledgments in 949 Ph.D. dissertations, 122 Master's Theses, and 670 Senior Theses that were submitted during Wheeler's career as an active mentor. By establishing a census of the students of the most active mentors at Princeton and Texas, it is possible to tabulate the publication record of these apprentice groups and obtain objective measures of mentoring efficacy. The dissertation concludes by discussing the wider applicability of the quantitative methodology and the qualitative analysis for the history of science and science studies

Review of Particle Physics

The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 3,062 new measurements from 721 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as supersymmetric particles, heavy bosons, axions, dark photons, etc. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as Higgs Boson Physics, Supersymmetry, Grand Unified Theories, Neutrino Mixing, Dark Energy, Dark Matter, Cosmology, Particle Detectors, Colliders, Probability and Statistics. Among the 117 reviews are many that are new or heavily revised, including new reviews on Pentaquarks and Inflation. The complete Review is published online in a journal and on the website of the Particle Data Group (http://pdg.lbl.gov). The printed PDG Book contains the Summary Tables and all review articles but no longer includes the detailed tables from the Particle Listings. A Booklet with the Summary Tables and abbreviated versions of some of the review articles is also available.The publication of the Review of Particle Physics is supported by the Director, Office of Science, Office of High Energy Physics of the U.S. Department of Energy under Contract No. DE–AC02–05CH11231; by the European Laboratory for Particle Physics (CERN); by an implementing arrangement between the governments of Japan (MEXT: Ministry of Education, Culture, Sports, Science and Technology) and the United States (DOE) on cooperative research and development; by the Institute of High Energy Physics, Chinese Academy of Sciences; and by the Italian National Institute of Nuclear Physics (INFN).The authors are grateful to Vincent Vennin for his careful reading of this manuscript and preparing Fig. 23.3 for this review. The work of J.E. was supported in part by the London Centre for Terauniverse Studies (LCTS), using funding from the European Research Council via the Advanced Investigator Grant 267352 and from the UK STFC via the research grant ST/L000326/1. The work of D.W. was supported in part by the UK STFC research grant ST/K00090X/1

Review of particle physics

The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 3,062 new measurements from 721 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as supersymmetric particles, heavy bosons, axions, dark photons, etc. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as Higgs Boson Physics, Supersymmetry, Grand Unified Theories, Neutrino Mixing, Dark Energy, Dark Matter, Cosmology, Particle Detectors, Colliders, Probability and Statistics. Among the 117 reviews are many that are new or heavily revised, including those on Pentaquarks and Inflation. The complete Review is published online in a journal and on the website of the Particle Data Group (http://pdg.lbl.gov). The printed PDG Book contains the Summary Tables and all review articles but no longer includes the detailed tables from the Particle Listings. A Booklet with the Summary Tables and abbreviated versions of some of the review articles is also available