need some topics on antenna for my thesis

hello

I would like to do my thesis on the topic ANTENNA. Earlier, i have simulated an RFID tag antenna in HFSS... Please help me giving some good topics on antenna for my thesis...

These subjects might interest a reader. (I'm not sure of the answers myself.)

* What travels between a radio transmitter and receiver? Is it a magnetic flux, or is it photons?

* Does an antenna necessarily need to be struck by photons, in order to detect a transmission?

* How many different sizes (in terms of fraction of a wavelength) can antennas be constructed, and work optimally?