Kaluza-Klein Masses and Couplings: Radiative Corrections to Tree-Level Relations

ORAL

Abstract

The most direct experimental signature of a compactified extra dimension is the appearance of an infinite tower of Kaluza-Klein particles. For example, a single flat extra dimension compactified on a circle leads to Kaluza-Klein states whose masses are integral multiples of the compactification scale and whose couplings are independent of the mode number. However, these masses and couplings are subject to radiative corrections. In this talk, I investigate the extent to which such radiative corrections deform the expected tree-level relations between Kaluza-Klein masses and couplings. As toy models for our analysis, I investigate a five-dimensional scalar $\phi^4$ model and a five-dimensional Yukawa theory involving both scalars and fermions. In each case, I identify the conditions under which the tree-level relations are stable to one-loop order, and the situations in which radiative corrections distort these relations by introducing entirely new dependences on mode number. One unexpected result is that the squared masses of the fermions in Yukawa theory receive corrections that actually grow with mode number. Another is that a $\gamma^5$ interaction is radiatively induced in this theory. Although small, such corrections to the Kaluza-Klein spectrum can therefore distort the measurement of the apparent geometry of a large extra dimension, and may be observable at future colliders. Along the way, I also develop several new calculational techniques for renormalization in higher dimensions.

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Authors

  • Stanley C. Solomon

    University of California and Lawrence Berkeley National Laboratory, Rutgers University, Utah State University, Brigham Young University, University of Utah, NASA, Duke University, FMA Research, Colorado State University, Dartmouth University, Idaho State University, Physics Department, Idaho State University, Physics Department, Utah State University, Los Alamos National Laboratory, Department of Physics, Nanjing University, China, University of California at Riverside, Physics Department, Colorado School of Mines, Physics Department, University of Utah, University of Nebraska - Lincoln, USU, Society of Physics Students, Arizona State University, Institute for Materials Science (NIMS), Namiki 1-1, Tsukuba, Ibaraki 305-0044, Japan, LANSCE-LC, Los Alamos National Laboratory, Van der Waals-Zeeman Institute, University of Amsterdam, Chemistry and Physics Dept., Virginia State University, University of Saskatchewan, Canada, Chalk River Laboratories, Physics Dept, Oxford University, Physics Dept, Utah State University, Sandia National Laboratories, National Renewable Energy Laboratory, DOE Center for Integrated Nanotechnologies, Sandia National Laboratories, National Center for Atmospheric Research