Tomorrow Yuxiang will tell us about his latest preprint (see below). 

The zoom link is https://ethz.zoom.us/j/362994444.

Best,

-joe

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Ultimate limit on time signal generation

The generation of time signals is a fundamental task in science. Here I will talk about the relation between the quality of a time signal and the physics of the system that generates it. According to quantum theory, any time signal can be decomposed into individual quanta that lead to single detection events. Our main result is a bound on how sharply peaked in time these events can be, which depends on the dimension of the signal generator. I will also discuss how the result may lead to a more accurate clock in the future.