Due to the SNCF metric, you will probably have to come to Caen via Paris. In this case, the best option is to take the train at the Station "Paris-Saint-Lazare". The station is accessible by metro lines 3, 12, 13 and 14.
To get to the Math Department from the Caen train station take the tramway A in the direction of Campus 2 and get off at the last stop.
The conference will take place in the Sciences 3 building (S3) of the Campus 2 of the University of Caen. A map of the campus is here.