Abstract
We give two examples of complex spaces on which global holomorphic functions separate points and give local coordinates and they cannot be realized as open subsets of Stein spaces. At the same time we notice that these examples are open subsets of Stein schemes, a notion introduced by Grauert (Math Z 81:377–391, 1963). In the context of complex schemes we notice that by contracting a Nori string one obtains a complex scheme and not a complex space. The covering spaces of 1-convex surfaces are divided in two categories: those that have an envelope of holomorphy and those that do not. More interesting are those in the second category and they correspond to covering spaces for singularities which in the desingularization with normal crossings contain cycles in the exceptional set.
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Acknowledgments
Both authors were partially supported by CNCS grant PN-II-ID-PCE-2011-3-0269.
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Dedicated to the memory of Professor Hans Grauert.