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arXiv · 2608.25885

The C{\oe}ur\'e-Loeb example as an open subset of a Stein space

Ovidiu Preda
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Abstract

The Serre problem asked if a locally trivial holomorphic fibration with Stein base and Stein fiber is itself Stein. \v Skoda constructed the first counterexample for this problem. Later, C{\oe}ur\'e and Loeb constructed another remarkable counterexample, with bounded domain of holomorphy as fiber. The total space of their fibration has global holomorphic functions which separate points and provide local coordinates. However, it does not admit a Stein envelope of holomorphy. In this paper, we prove that the C{\oe}ur\'e--Loeb fibration can be realized as an open subset of a Stein space, more precisely it is the complement of an analytic set in a Stein space.

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Ovidiu Preda. 2026-08-26. The C{\oe}ur\'e-Loeb example as an open subset of a Stein space. https://arxiv.org/abs/2608.25885

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