@Bellatrix I agree.
When we are faced with situations that we have been told to keep quiet about they are usually to cover up for someone or something.
There are times when we know for sure that someone is lying or being deceptive, and we will accept the lie in fear of appearing outspoken.
IMO you should not accept deception or lies. I’m sure they would offer either an explination or withdrawal if they were challenged.
If I was to be found wrong about them I would apologise, at least people know that they are going to be challenged and may think twice before being dishonest.
However @wundayatta you sound like it isn’t bothering you too much.
Look at this perspective:
I am a professor am I imagining attraction?
Shares my Strong and prolonged eye contact without complaint .Dosen’t mind Finger touching every time an object is exchanged when there are definite and easy ways to avoid contact.Doesn’t mind being guided by a hand on the back or by the arm. They ask Personal questions (are you married do you have kids?). Possibly subtle teasing (not sure).
Flirting or normal behavior? I guess it could go either way. Some people just make good eye contact and ask questions to get to know a person. The other two seem a little in the gray area… But from a single student ? Although there is not much age difference.
In any case, I think we at least have great chemistry as colleagues and could possibly see us being good (platonic!) friends.
There are a mulitude of possible answers to your thoughts. I think your actions and questions towards the professor might reap the desired understanding that you are looking for.