Out of the Vacuum: A Hidden Assumption

摘要

She swept through my open office door around noon with a question.The textbook statement she was asked to prove for homework [1, page 114,Exercise 4.10] was written as a theorem, which in mathematics means a truestatement for which a proof is known. So, taking the authors at their word,barring any unintended error in this third edition of the text, she confidentlyengaged in the task of finding such a proof.