In this task, based on the given input, we ask you to write a question about when an event happened. Your question should be answerable with common knowledge on when events usually take place. For example, "going to school" usually happens during the day (not at 2 A.M). Don't create questions which have explicit mentions of answers in the text. Instead, it has to be implied from what is given. In other words, we want you to use "instinct" or "common sense". The written questions are not required to have a single correct answer.
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Question: Sentence: Einstein discovered Louis de Broglie's work, and supported his ideas, which were received skeptically at first.

Answer: When did Einstein discover Louis' work?


Question: Sentence: The massive ice sheet, called a glacier, caused the features on the land you see today.

Answer: When did the glacier start impacting the land's features?


Question: Sentence: In another major paper from this era, Einstein gave a wave equation for de Broglie waves, which Einstein suggested was the Hamilton-Jacobi equation of mechanics.

Answer:
What time did Einstein publish his wave equation?


