arXiv:1001.1163v1 [hep-ph] 8 Jan 2010 1 It is an important question whether the final/initial state gluonic interactions which lead to naive- time-reversal-odd single-spin asymmetries and diffraction at leading twist can be associated in a definite way with the light-front wave function hadronic eigensolutions of QCD. We use light-front time-ordered perturbation theory to obtain augmented light-front wave functions which contain an imaginary phase which depends on the choice of advanced or retarded boundary condition for the gauge potential in light-cone gauge. We apply this formalism to the wave functions of the valence Fock states of nucleons and pions, and show how this illuminates the factorization properties of naive-time-reversal-odd transverse momentum dependent observables which arise from rescattering. In particular, one calculates the identical leading-twist Sivers function from the overlap of augmented light-front wavefunctions that one obtains from explicit calculations of the single-spin asymmetry in semi-inclusive deep inelastic lepton-polarized nucleon scattering where the required phases come from the final-state rescattering of the struck quark with the nucleon spectators. PACS numbers: Phases of Augmented Hadronic Light-Front Wave Functions SLAC-PUB-13874 Stanley J. Brodsky, 1 Barbara Pasquini, 2 Bo-Wen Xiao, 3 and Feng Yuan 3, 4 $^{1}$SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94309 $^{2}$Dipartimento di Fisica Nucleare e Teorica, Universit` a degli Studi di Pavia, and INFN, Sezione di Pavia, Italy $^{3}$Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 $^{4}$RIKEN BNL Research Center, Building 510A, Brookhaven National Laboratory, Upton, NY 11973 Abstract