Introduction

Attention: Imperial physicist's ground breaking work in 1960s recognised by journal, Nobelist Steven Weinberg Praises Professor Gerald Guralnik and Collaborators for Higgs Boson Theory and Profs. try to solve mysteries of universe; for more on this, read A Physics History of My part in the Theory of Spontaneous Symmetry Breaking and Gauge particles with a mix of modern ideas (PDF, 194Kb).

Welcome to the Computational High Energy Physics (CHEP) group page. We pursue alternative, complementary approaches to numerical quantum field theory to those methods based on Monte Carlo approximations of the functional Feynman Path Integral.

Presently, our work is primarily focused on 2 novel numerical methods and 1 analytical line of research:

• Source-Galerkin: consists of obtaining `best' approximations, via methods of weighted residuals, to solutions of the Schwinger-Dyson equations. In the course of this work, we have asked many (and convincingly answered a few) questions concerning the basic formulation of quantum field theories. (The code for some of these computations can be found in this link.)
• Mollifier Technique: consists of smoothing out the highly oscillatory terms in the [Minkowski] path integral, thus rendering it possible to compute it via a proper Monte Carlo. As before, many question have been (and are in the process of being) asked [regarding the foundations of QFT] and some have found its answers.
• Symmetry Breaking and Topology Change: String Theory has reached a problematic stage where its answers — the different vacua that solve the theory — are the minimum of a potential landscape. Given that, as of now, there are possibly a vast number of physically allowed vacua, the phase structure of the theory is potentially very rich. In order to study this phase structure and its spontaneous symmetry breakings, we have developed a novel approach that lifts QFT to a new geometrical stance. This, in turn, enables us to show that different phases of the theory have topologically inequivalent configuration spaces, which, for String Theory, gives birth to topologically inequivalent Universes. In order to accomplish this, we use a conformal transformation historically used by Jacobi with a twofold purpose: unify Hamilton's (mechanics) and Fermat's (optics) action principles into a single framework and turn every hamiltonian flow into a geodesic one.

On this page, we provide descriptions and pointers of recent publications, to member home pages, and to group facilities. Further information about the CHEP group can be obtained by sending inquiries to chep-info [at] het [dot] brown [dot] edu.

General Information

• Some general information on lattice physics can be found here (PS, 263Kb) or here (PDF, 338Kb) (by Daniel D Ferrante) and here (by Kostas Orginos).
• Also, you can read the sci.physics.research [Usenet] newsgroup or the Physics FAQ.

Members

Publications & Talks

• arXiv & SPIRES HEP:
  • Richard Easther;
  • Pinar Emirdag;
  • Daniel D. Ferrante;
  • Gerald S. Guralnik;
  • Zachary Guralnik.
  • Stephen Hahn;
  • Cengiz Pehlevan;
  • Dmitri Petrov.
• 2006:
  1. Daniel D. Ferrante, Gerald S. Guralnik; Mollifying Quantum Field Theory or Lattice QFT in Minkowski Spacetime and Symmetry Breaking. Note that the version available from the arXivs has low resolution figures; a [properly formatted] high resolution of this work can be found in the following links: [ PDF (5.1Mb) | PS (23Mb) ].
  2. 2º CAINBRA (Conferência Anual Interdisciplinar dos Brasileiros na Brown): Daniel D. Ferrante, "O que é massa: da Relatividade à Mecânica Quântica".
  3. Daniel D. Ferrante, Gerald S. Guralnik; From Symmetry Breaking to Topology Change I. Note that the version available from the arXivs does not have the internal PDF links properly set up (although their PS version is fine); a better PDF file can be found in the following link: [ PDF (527Kb) ].
• 2005:
  1. 1º CAINBRA (Conferência Anual Interdisciplinar dos Brasileiros na Brown): Daniel D. Ferrante, "Geometrizando a Mecânica Quântica", [ PDF (396Kb) ].
• 2004:
  1. Astrophysical Journal Club: Daniel D. Ferrante, "Loop Quantum Cosmology", [ PDF (207Kb) | HTML (14Kb) ];
  2. CHEP Research Review talk: Daniel D. Ferrant and Gerald S. Guralnik, DoE '04, [ PDF (3.6Mb) | PS (3.5Mb) ];
  3. Daniel D. Ferrante and Gerald S. Guralnik, "Poster on the Recent CHEP Research": [ PS (329Kb) | PDF (259Kb) ].
• 2003:
  1. Gerald S. Guralnik, A. Iorio, R. Jackiw and S. Y. Pi; Dimensionally Reduced Gravitational Chern-Simons Term and its Kink;
  2. Richard Easther, Daniel D. Ferrante, Gerald S. Guralnik and Dmitri Petrov; A Review Of Two Novel Numerical Methods in QFT;
  3. Daniel D. Ferrante, Generalized Bundle Quantum Mechanics (invited contribution to "Progress in Quantum Physics Research", to be published by Nova Science Publishers, Inc., New York);
  4. Daniel D. Ferrante, Gerald S. Guralnik and Dmitri Petrov, "Poster on the Recent CHEP Research": [ PS (1.6Mb) | PDF (541Kb) ].
• 2002:
  1. Washington University [Physics Colloquium]: Gerald S. Guralnik; "A Physics History of My part in the Theory of Spontaneous Symmetry Breaking and Gauge particles with a mix of modern ideas"; [ PDF (194Kb) ].
  2. Daniel D. Ferrante, Geometric Calculus and the Fibre Bundle description of Quantum Mechanics;
  3. Cornell University [Applied Math Colloquium]: Gerald S. Guralnik; "Computing to Learn Physics while watching computers grow up"; [ PS (185Kb) | PDF (190Kb) ];
  4. Lattice 2002: Daniel D. Ferrante, "Stationary Phase Monte Carlo Methods"; [ PS (1.4Mb) | PDF (569Kb) ];
  5. Lattice 2002: Gerald S. Guralnik, "Alternative Numerical Techniques"; [ PS (152Kb) | PDF (152Kb) ];
  6. Lattice 2002: Dmitri Petrov, "A Test of The Source Galerkin Method";
  7. UFC (Universidade Federal do Ceará, Brasil - 29Jul02/02Ago02): Daniel D. Ferrante, "Mollified Monte Carlo (Parts I and II)"; [ PS (2.9Mb) | PDF (1.1Mb) ];
  8. UFC (Universidade Federal do Ceará, Brasil - 29Jul02/02Ago02): Daniel D. Ferrante, "Branes: An Introduction (Parts I and II)"; [ PS (373Kb) | PDF (308Kb) ];
  9. Daniel D. Ferrante, J. D. Doll, D. Sabo, Gerald S. Guralnik; Mollified Monte Carlo;
  10. Gerald S. Guralnik, J. D. Doll, Richard Easther, Pinar Emirdag, Daniel D. Ferrante, Stephen Hahn, Dmitri Petrov and D. Sabo; Alternative Numerical Techniques;
  11. Dmitri Petrov, Pinar Emirdag and Gerald S. Guralnik; A Test of The Source Galerkin Method; &
  12. Astrophysical Journal Club: Daniel D. Ferrante, "The Effects of Spacetime on Yang-Mills Theories"; [ PS (268Kb) | PDF (290Kb) ].
• 2001:
  1. Pinar Emirdag, Richard Easther, Gerald S. Guralnik, Stephen C. Hahn and Dmitri Petrov; Numerical Quantum Field Theory on the Continuum and a New Look at Perturbation Theory.
• 2000:
  1. Dmitri Petrov, Richard Easther, Gerald Guralnik, Stephen Hahn, Wei-Mun Wang; Fermions, Gauge Theories, and the Sinc Function Representation for Feynman Diagrams.
• 1999:
  1. Pinar Emirdag, Richard Easther, Gerald S. Guralnik and Stephen C. Hahn; New Numerical Methods for Quantum Field Theories on the Continuum;
  2. Richard Easther, Gerald S. Guralnik and Stephen C. Hahn; The Sinc Function Representation and Three-Loop Master Diagrams; &
  3. Richard Easther, Gerald S. Guralnik and Stephen C. Hahn; Fast Evaluation of Feynman Diagrams.
• 1998:
  1. Stephen C. Hahn and Gerald S. Guralnik, Numerical field theory on the continuum; &
  2. Stephen C. Hahn and Gerald S. Guralnik, New numerical methods for iterative or perturbative solution of quantum field theory.
• 1996:
  1. AUP Quantum Chromodynamics Workshop in Paris: Gerald S. Guralnik, "Source driven solutions of quantum field theories"; PS (123Kb) or PDF (143Kb);
  2. AUP Quantum Chromodynamics Workshop in Paris: Zachary Guralnik, Multiple Vacua and Boundary Conditions for Schwinger-Dyson equations;
  3. Coral Gables Conference: Gerald Guralnik, "Numerical quantum field theory using the source Galerkin method"; PS (109Kb) or PDF (134Kb); &
  4. Coral Gables Conference: Zachary Guralnik, "Boundary conditions for Schwinger-Dyson equations and vacuum selection"; PS (99Kb) or PDF (109Kb).
• 1995:
  1. John W. Lawson and G. S. Guralnik, New Numerical Method for Fermion Field Theory; &
  2. John W. Lawson and G. S. Guralnik, Source Galerkin Calculations in Scalar Field Theory.
• 1993:
  1. S. García, G. S. Guralnik, and J. W. Lawson, A New Method for Numerical Quantum Field Theory.

Facilities

CHEP is a major participant in the Theoretical Physics Computing Facility at Brown University, directing funds from the Department of Energy towards the purchase of two Cray medium-scale supercomputer platforms, as well as a collection of workstations (Intel, AMD, Sun) for code development and data analysis.

For production work, the group uses the remote large-scale supercomputing facilities at NERSC. We are beginning investigations into massively parallel algorithms, as applied to our large sets of nonlinear equations.

Help and Manuals

If you are a begginer [a newbie, a tidbit], HET Help is for you! ;-)

If you need help with *nix (Unix, GNU/Linux, Solaris, Irix, etc...) commands (mainly GNU applications), please try any of the following links: