Quantum Electrodynamics Interpolated Between Instant Form and Front Form

ORAL

Abstract

Among the three forms of relativistic dynamics proposed by Dirac in1949, the front form of relativistic dynamics now known as the light-front dynamics (LFD) appears to have definite advantages over the instant form dynamics, when it deals with the hadronic processes where the relativistic effects are significant. In particular, LFD may save a substantial dynamical effort put in the instant form dynamics with respect to getting the QCD solutions that reflect the full Poincar\'e symmetries, due to the built-in boost invariance and simpler vacuum property. As an effort to understand how the familiar instant form dynamics (IFD) transforms to LFD, we interpolate the two forms of dynamics by introducing an interpolation angle that changes the ordinary time $t$ to light front time $(t+z/c)\sqrt{2}$. In this presentation, we report our derivation of the polarization vectors for photon and the helicity spinors for spin-1/2 fermion that interpolate between IFD and LFD and the application of our results to the lowest-order QED scattering amplitudes. Our analysis makes clear the distinction between the infinite momentum frame (IMF) and the LFD.

–

Authors

  • Ziyue Li

    North Carolina State University

  • Murat An

    North Carolina State Univ, North Carolina State University

  • Chueng-Ryong Ji

    North Carolina State University

  • J.K. Hwang

    Western Kentucky University, University of Pardubice, Francis Marion University, Clemson University Professor, Francis Marion University Professor, Undergraduate Administrator, Oak Ridge National Laboratory, Oak Ridge, Tennessee, Austin Peay State University, University Strenwarte-Muenchen, Seoul National University, Gatton Academy for Science and Mathematics, Alabama A\&M University, Cygnus, Center for Nanophase Materials Science at Oak Ridge National Laboratory, Vanderbilt University, Fisk Univ, 2Cornell High Energy Synchrotron Source, Cornell University, Ithaca, NY, NOVA Center, Western Kentucky University, Department of Physics, Florida A\&M University, Tallahassee, FL-32307, Correlated Electron Materials Group, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6061 USA, Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville, TN 37235, USA, Department of Electrical and Computer Engineering, University of Rochester, Rochester, NY 14627, USA, The Institute of Optics, University of Rochester, Rochester, NY 14627, USA, Universidade Estadual Paulista (UNESP), Clark Atlanta University, Deapartment of Physics \& Astronomy, Georgia State University, USA, Department of Electrical and Computer Engineering, McGill University, Montreal, QC H3A 2A7, Canada, Oak Ridge National Laboratory, University of South Alabama, Samford University, University of Rochester, University of North Carolina, Chapel Hill, Sandia National Laboratories, New Mexico State University, University of Tennessee Space Institute, Shanghai Jiao Tong University, Shanghai, China, University of Leeds, Leeds, UK, Georgia State University, Atlanta GA, University of Alabama at Birmingham, National High Magnetic Field Laboratory, Prairie View A\&M University, Brookhaven National Laboratory, University of Southern Indiana, Center for Nanophase Materials Sciences at Oak Ridge National Laboratory, JINR(Dubna), Tsinghua Univ., LBNL, Vanderbilt Univ., Vanderbilt Univ./Univ. of Tennessee, Knoxville, Vanderbilt Univ./Univ. of Kentucky, GANIL, Vanderbilt Univ./Union Univ., JINR, ORAU, Tsinghua University, LNBL