activity
20232025
collaborators

5 papers

math.AP2025

Nonlinear nonlocal equations in Reifenberg flat domains

Sun-Sig Byun, Kyeongbae Kim, Kyeong Song

We consider nonhomogeneous fractional -Laplace equations defined on a bounded nonsmooth domain which goes beyond the Lipschitz category. Under a sufficient flatness assumption o…

math.AP2024

Global Calderón-Zygmund theory for fractional Laplacian type equations

Sun-Sig Byun, Kyeong Bae Kim, Deepak Kumar

We establish several fine boundary regularity results of weak solutions to non-homogeneous -fractional Laplacian type equations. In particular, we prove sharp Calderón-Zygmund t…

math.AP2023

Calderón-Zygmund theory of nonlocal parabolic equations with discontinuous coefficients

Sun-Sig Byun, Kyeongbae Kim, Deepak Kumar

We prove Calderón-Zygmund type estimates of weak solutions to non-homogeneous nonlocal parabolic equations under a minimal regularity requirement on kernel coefficients. In particu…

math.AP2023

Higher Hölder regularity for nonlocal parabolic equations with irregular kernels

Sun-Sig Byun, Hyojin Kim, Kyeongbae Kim

We study a nonlocal parabolic equation with an irregular kernel coefficient to establish higher Hölder regularity under an appropriate higher integrablilty on the nonhomogeneous te…

math.AP2023

Regularity results for a class of nonlocal double phase equations with VMO coefficients

Sun-Sig Byun, Kyeongbae Kim, Deepak Kumar

We study a class of nonlocal double phase problems with discontinuous coefficients. A local self-improving property and a higher Hölder continuity result for weak solutions to such…