Quantization of fourform fluxes and dynamical neutralization of the cosmological constant
Abstract
A fourform gauge flux makes a variable contribution to the cosmological constant. This has often been assumed to take continuous values, but we argue that it has a generalized Dirac quantization condition. For a single flux the steps are much larger than the observational limit, but we show that with multiple fluxes the allowed values can form a sufficiently dense `discretuum'. Multiple fluxes generally arise in Mtheory compactifications on manifolds with nontrivial threecycles. In theories with large extra dimensions a few fourforms suffice; otherwise of order 100 are needed. Starting from generic initial conditions, the repeated nucleation of membranes dynamically generates regions with lambda in the observational range. Entropy and density perturbations can be produced.
 Publication:

Journal of High Energy Physics
 Pub Date:
 June 2000
 DOI:
 10.1088/11266708/2000/06/006
 arXiv:
 arXiv:hepth/0004134
 Bibcode:
 2000JHEP...06..006B
 Keywords:

 High Energy Physics  Theory;
 Astrophysics;
 General Relativity and Quantum Cosmology;
 High Energy Physics  Phenomenology
 EPrint:
 30 pages, 1 figure. v2: minor changes, references added