Falling in love is a common experience and a wonderful one. It sweeps us up in a euphoric passion that dominates our thoughts day and night. But is there more to it than simple emotions?   Romantic love, and its impact on us, has been the subject of study for millennia. Philosophers from ancient times have mused on it, theologians have divined it and poets have waxed lyrical about it.   More recently, it has become a subject of interest to scientists from the fields of psychology, sociology and neurobiology. Consequently, we ...