I'm new here and it was suggested to me to ask this here. There was a particular user who's answers and questions came up more than once when researching a couple math related topics and I was hoping to ask if they would like to collaborate with myself and other mathematicians on furthering a particular research area.
So, I signed up for an account here, but then there appears to be no messaging system. Then I figured maybe if I left a comment it would alert them, but it won't let me comment on their posts. How could I contact a specific user? Maybe there is a way to start a chat room and invite them or something along those lines?