Real Algebraic Threefolds Iv. Del Pezzo Fibrations
نویسنده
چکیده
This paper continues the study of the topology of real algebraic threefolds begun in [Kollár97b, Kollár97c, Kollár98a], but the current work is independent of the previous ones in its methodology. The present aim is to understand the topology of the set of real points of threefolds which admit a morphism to a curve whose general fiber is a rational surface. This class of threefolds also appears as one of the 4 possible outcomes of the minimal model program (cf. [Kollár-Mori98, Sec. 3.7]). Our main theorem gives a nearly complete description of the possible topological types of the set of real points of such a threefold in the orientable case.
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تاریخ انتشار 1999