Depth of $F$-singularities and base change of relative canonical sheaves

  title={Depth of \$F\$-singularities and base change of relative canonical sheaves},
  author={Zsolt Patakfalvi and Karl Schwede},
  journal={Journal of the Institute of Mathematics of Jussieu},
  pages={43 - 63}
Abstract For a characteristic-$p\gt 0$ variety $X$ with controlled $F$-singularities, we state conditions which imply that a divisorial sheaf is Cohen–Macaulay or at least has depth $\geq $3 at certain points. This mirrors results of Kollár for varieties in characteristic 0. As an application, we show that relative canonical sheaves are compatible with arbitrary base change for certain families with sharply $F$-pure fibers. 
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