skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Compactification and signature transition in Kaluza-Klein spinor cosmology

Journal Article · · Annals of Physics (New York)
 [1];  [1];  [2]
  1. Department of Physics, Shahid Beheshti University, Evin, Tehran 19839 (Iran, Islamic Republic of)
  2. Department of Physics, Shahid Beheshti University, Evin, Tehran 19839 (Iran, Islamic Republic of) and Institute for Studies in Theoretical Physics and Mathematics, P.O. Box 19395-5746, Tehran (Iran, Islamic Republic of)

We study the classical and quantum cosmology of a 4 + 1-dimensional space-time with a non-zero cosmological constant coupled to a self-interacting massive spinor field. We consider a spatially flat Robertson-Walker universe with the usual scale factor R (t) and an internal scale factor a (t) associated with the extra dimension. For a free spinor field the resulting equations admit exact solutions, whereas for a self-interacting spinor field one should resort to a numerical method for exhibiting their behavior. These solutions give rise to a degenerate metric and exhibit signature transition from a Euclidean to a Lorentzian domain. Such transitions suggest a compactification mechanism for the internal and external scale factors such that a {approx} R {sup -1} in the Lorentzian region. The corresponding quantum cosmology and the ensuing Wheeler-DeWitt equation have exact solutions in the mini-superspace when the spinor field is free, leading to wavepackets undergoing signature change. The question of stabilization of the extra dimension is also discussed.

OSTI ID:
20845935
Journal Information:
Annals of Physics (New York), Vol. 321, Issue 11; Other Information: DOI: 10.1016/j.aop.2006.04.016; PII: S0003-4916(06)00109-6; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-4916
Country of Publication:
United States
Language:
English