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Regularity estimates for the gradient flow of a spinorial energy functional

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 Added by Changliang Wang
 Publication date 2019
  fields
and research's language is English




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In this note, we establish certain regularity estimates for the spinor flow introduced and initially studied in cite{AWW2016}. Consequently, we obtain that the norm of the second order covariant derivative of the spinor field becoming unbounded is the only obstruction for long-time existence of the spinor flow. This generalizes the blow up criteria obtained in cite{Sc2018} for surfaces to general dimensions. As another application of the estimates, we also obtain a lower bound for the existence time in terms of the initial data. Our estimates are based on an observation that, up to pulling back by a one-parameter family of diffeomorphisms, the metric part of the spinor flow is equivalent to a modified Ricci flow.

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