  We present observational evidence for oscillations of magnetic flux density
in the quiet areas of the Sun. The majority of magnetic fields on the solar
surface have strengths of the order of or lower than the equipartition field
(300-500 G). This results in a myriad of magnetic fields whose evolution is
largely determined by the turbulent plasma motions. When granules evolve they
squash the magnetic field lines together or pull them apart. Here we report on
the periodic deformation of the shapes of features in circular polarization
observed at high resolution with Sunrise. In particular, we note that the area
of patches with constant magnetic flux oscillates with time, which implies that
the apparent magnetic field intensity oscillates in antiphase. The periods
associated to this oscillatory pattern is compatible with the granular
life-time and change abruptly, which suggests that these oscillations might not
correspond to characteristic oscillatory modes of magnetic structures, but to
the forcing by granular motions. In one particular case, we find three patches
around the same granule oscillating in phase, which means that the spatial
coherence of these oscillations can reach 1600 km. Interestingly, the same kind
of oscillatory phenomenon is found also in the upper photosphere.
