The decoupling surface in relativistic heavy-ion collisions may not be
homogeneous. Rather, inhomogeneities should form when a rapid transition from
high to low entropy density occurs. We analyze the hadron "chemistry" from
high-energy heavy-ion reactions for the presence of such density
inhomogeneities. We show that due to the non-linear dependence of the particle
densities on the temperature and baryon-chemical potential such inhomogeneities
should be visible even in the integrated, inclusive abundances. We analyze
experimental data from Pb+Pb collisions at CERN-SPS and Au+Au collisions at
BNL-RHIC to determine the amplitude of inhomogeneities and the role of local
and global strangeness neutrality.Comment: 8 pages, 6 figures, To appear in proceedings of the workshop on
'Particle Correlations and Femtoscopy' September 9-11, 2006, Sao Paulo,
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