發送短信 : Harnack inequality under the change of metric

  _  __     ___     _    _     _____     ____    
 | |/ //   / _ \\  | \  / ||  |  ___||  |  _ \\  
 | ' //   / //\ \\ |  \/  ||  | ||__    | |_| || 
 | . \\  |  ___  ||| .  . ||  | ||__    | .  //  
 |_|\_\\ |_||  |_|||_|\/|_||  |_____||  |_|\_\\  
 `-` --` `-`   `-` `-`  `-`   `-----`   `-` --`