Rav Shurkin asked a question on the zoom shiur on Sunday, Aug 15: the heter for pikuach nefesh is learned out from the words וחי בהם - ולא שימות בהם.  We also find the same words in Parshas Vaeschanan by a רוצח בשוגג, and the Rambam learns out from these words that the רוצח's rebbe must go into golus too - because חיים without Torah isn't חיים.

If so, asked Rav Shurkin, why can't a talmid be mechalel Shabbos to hear a shiur from his Rebbe, since חיים without Torah is like מיתה?

What's the answer?