Tango Structures on Curves in Characteristic 2

Conference paper
Part of the Springer Proceedings in Mathematics & Statistics book series (PROMS, volume 319)


The (pre-)Tango structure is a certain ample invertible sheaf of exact differential 1-forms on a projective algebraic variety and it implies some typical pathological phenomena in positive characteristic. Moreover, by using the notion of (pre-)Tango structure, we can construct another variety accompanied by similar pathological phenomena. In this article, we explicitly show several interesting and mysterious phenomena on the induced uniruled surfaces from (pre-)Tango structures on curves in characteristic 2.


Characteristic 2 Pathological phenomenon Tango structure Non-closed differential form Non-reduced automorphism group scheme 


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Authors and Affiliations

  1. 1.Department of Mathematics and StatisticsWakayama Medical UniversityWakayamaJapan

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