Polarization swings from curved trajectories of the emitting regions
  We present a model of polarization swings in blazars from axially symmetric
blobs propagating on curved trajectories. If the minimum inclination of the
velocity vector to the line of sight is smaller than Gamma^{-1}, the
polarization angle maximum rotation rate is simultaneous with the polarization
degree minimum and a spike in the total flux. By measuring the maximum rotation
rate and the moment of the polarization maximum, it is possible to estimate the
distance covered by the blob and thus its approximate position. We apply this
model to the recent polarization event in blazar 3C 279.
