You may only need 30 seconds to make a longterm, reliable judgement about a potential partner. Just ask Sean Horan, assistant professor in communication studies at Texas State University. His research shows that your first half-minute of meeting someone can be an accurate predictor of how you'll feel in the future (via Greatist). However, it's important to note that first impressions don't have to leave you completely sure. You don't need to be immediately physically attracted to a potential partner either. But it's not a great sign if you feel like bolting for the nearest exit, calling a cab, and booking the next flight out to Iceland after you've shared the same space with someone for a couple minutes.
Of course, during your first half-minute of getting-to-know-yous, discussing even the weather might be a stretch. What should you pay attention to? Eye contact is a good place to start. Susan Trombetti, CEO of Exclusive Matchmaking notes that the ability to maintain eye contact is both "an easy tell that you two have good chemistry" and also "helps create a sense of intimacy" (via Bustle).
You might also try grazing your potential partner's arm. No need to convince your future beau that it's a good idea to french kiss, Romeo and Juliet style. On the other hand, if you get a rush out of a touch on the shoulder or a hand placed timidly on the lower back, that's a solid indication that you're off to a good start (via Greatist).
