We study various boundary and inner regularity questions for -(super)harmonic functions in Euclidean domains. In particular, we prove the Kellogg property and introduce a classification of boundary points for -harmonic functions into three disjoint classes: regular, semiregular and strongly irregular points. Regular and especially semiregular points are characterized in many ways. The discussion is illustrated by examples.Along the way, we present a removability result for bounded -harmonic functions and give some new characterizations of spaces. We also show that -superharmonic functions are lower semicontinuously regularized, and characterize them in terms of lower semicontinuously regularized supersolutions.
@article{AIHPC_2014__31_6_1131_0, author = {Adamowicz, Tomasz and Bj\"orn, Anders and Bj\"orn, Jana}, title = {Regularity of $ p(\cdot )$-superharmonic functions, the Kellogg property and semiregular boundary points}, journal = {Annales de l'I.H.P. Analyse non lin\'eaire}, volume = {31}, year = {2014}, pages = {1131-1153}, doi = {10.1016/j.anihpc.2013.07.012}, mrnumber = {3280063}, zbl = {1304.35296}, language = {en}, url = {http://dml.mathdoc.fr/item/AIHPC_2014__31_6_1131_0} }
Adamowicz, Tomasz; Björn, Anders; Björn, Jana. Regularity of $ p(\cdot )$-superharmonic functions, the Kellogg property and semiregular boundary points. Annales de l'I.H.P. Analyse non linéaire, Tome 31 (2014) pp. 1131-1153. doi : 10.1016/j.anihpc.2013.07.012. http://gdmltest.u-ga.fr/item/AIHPC_2014__31_6_1131_0/
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