The institute of Theoretical and Computational Physics, as part of TU Graz, hosts two full professors, two associate professors, three assistant professors, as well as a number of PostDocs and PhD students.
Take tram no. 6, direction St Peter Schulzentrum, and exit at stop Neue Technik. Walk the Steyrergasse uphill, and you find the physics building on the left side at the next crossing with a traffic light. You can enter either from Steyrergasse or from Petersgasse.
There are several options, taking a taxi is for sure the quickest and most convenient one. However, there is also public transport from the airport to town: if you take the train, you will end up at the main train station, and you have to follow the description above. If you take the bus, it will take you to Jakominiplatz. From there, you can also take tram no. 6 as above. Fore more information about the transport from and to the airport, including timetables, you can visit the homepage of Graz Airport.