Zoom 회의 참가 https://snu-ac-kr.zoom.us/j/88537621552?pwd=SlBLMTRRdmhNWWVvR3NvWEZkbURoUT09 회의 ID: 885 3762 1552 암호: 896534 We will give a geometric treatment of the fundamental estimates for elliptic equations. A new geometric proof of DeGorgi-Nash theorem as well as geometric interpretations of Schaulder and Caldron-Zygmund estimates are discussed.