What questions to ask a famous mathematician A famous professor mathematician is coming to my city next week and will be doing a lecture with a Q&amp;A session afterwords. I’d like to ask a couple of questions afterwords but I’ve no idea what to say and don’t want to look silly in front of everyone else.
Do I ask them about things they researched? I’m really not sure.
What advice would you give to a youngster interested in math? To a college student?
What do you do to overcome frustration when the going gets hard?
What sort of problems interest you now? 
Where should I look for interesting problems? 
What was your first interesting encounter with math? 


other things like that. 

Of course, the talk might cover some of this but might also suggest other questions. 

Of course, if the talk is being given to specialists, rather than the public, then questions specific to the talk would be appropriate, but possibly difficult to prepare in advance.