Applying ideas of fractional analogue of Monge-Ampére operator by L. Caffarelli and F. Charro, we consider an analogue of fractional k-Hessian operators expressed as concave envelopes of fractional linear operators, and reproduce the same regularity results when k=2.
Under the set up of global solutions prescribing data at infinity and global barriers, the key estimate is to prove that fractional 2-Hessian operator is strictly elliptic. Then we can apply nonlocal Evans-Krylov theorem to prove such solutions are classical.
Fractional elementary symmetric functions and Hessian estimates in the plane
Mathematical Sciences Institute, Australian National University(澳大利亚国立大学数学科学学院);CNRS-ANU International Research Laboratory FAMSI(法国国家科学研究中心-澳大利亚国立大学FAMSI国际研究实验室);Department of Mathematics, The Chinese University of Hong Kong(香港中文大学数学系)
Sharp comparison between the perimeter and its fractional analogue in two dimensions
Ludwig-Maximilians Universität München(慕尼黑路德维希-马克西米利安大学);Munich Center for Quantum Science and Technology(慕尼黑量子科学与技术中心);University of California, Irvine(加州大学尔湾分校)
Sharp Stability for the Affine Fractional Sobolev Inequality
School of Mathematics and Statistics Guizhou University(贵州大学数学与统计学院);College of Mathematics and Statistics Chongqing Jiaotong University(重庆交通大学数学与统计学院)