On a recent Monday morning on the Upper West Side, a group of about 20 men and women sat in pairs, hunched over enormous Jewish legal tomes and dissecting their contents in animated conversation. It was a typical scene at Hadar, an egalitarian yeshiva that has run full-time study programs for young adults in New York City since 2007. Less typical was the mundane topic of their study: whether it is permissible to use a dishwasher for both meat and milk dishes in successive cycles. It’s the kind of question typically asked of synagogue rabbis.