If one makes matzo for Passover, an 18-minute window opens. The person (or machine) that prepares it has only 1,080 seconds from the time that the flour and water are mixed together until the time that the matzo is removed from the oven, before the entire batch must be thrown away—symbolic sin, in the form of fermentation, has crept into the dough.
This is a companion discussion topic for the original entry at https://spectrummagazine.org/article/midori-yoshimura/2013/03/29/sabbath-spectrum-caf%25c3%25a9