I have been studying the halachos  of borer  for the past three months and have come across some very fine points. There are a number of questions I would like to ask the rov , if possible. Thank you. Chaim Tzvi Uzvolk Rubik’s Cube Revisited Question A number of years ago, I read an article in the Yated  where the rov permitted playing with a Rubik’s Cube on Shabbos . Recently, there was a sefer  published on borer  which cites, in the rov ’s name, that it is forbidden to pla