Abstract
In [2], Hardt, Lin and the author proved that the defect set of minimizers of the modified Ericksen energy for nematic liquid crystals consists locally of a finite union of isolated points and Hölder continuous curves with finitely many crossings. In this article, we show that each Hölder continuous curve in the defect set is of finite length. Hence, locally, the defect set is rectifiable. For the most part, the proof closely follows the work of De Lellis et al. (Rectifiability and upper minkowski bounds for singularities of harmonic q-valued maps, arXiv:1612.01813, 2016) on harmonic \({\mathcal{Q}}\)-valued maps. The blow-up analysis in Alper et al. (Calc Var Partial Differ Equ 56(5):128, 2017) allows us to simplify the covering arguments in [11] and locally estimate the length of line defects in a geometric fashion.
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Alper, O. Rectifiability of Line Defects in Liquid Crystals with Variable Degree of Orientation. Arch Rational Mech Anal 228, 309–339 (2018). https://doi.org/10.1007/s00205-017-1193-1
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DOI: https://doi.org/10.1007/s00205-017-1193-1