The Hasse-Witt invariant in some towers of function fields over finite fields

  • A. Bassa
  • P. Beelen


In this article we investigate the p-rank of function fields in several good towers. To do this we first recall and establish some properties of the behaviour of the p-rank under extensions. Then we compute the p-ranks of function fields in several optimal towers over a quadratic field \( \mathbb{F}_{q^2 } \), as well as for a specific good tower over a cubic field \( \mathbb{F}_{q^3 } \), which was introduced by Bassa, Garcia and Stichtenoth.


towers of function fields Zink’s bound Hasse-Witt invariant p-rank 

Mathematical subject classification

14H05 11G20 14G50 14G35 


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Copyright information

© Springer 2010

Authors and Affiliations

  1. 1.CWIAmsterdamThe Netherlands
  2. 2.DTU-MathematicsKgs. LyngbyDenmark

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