Recent experimental developments in quantum optics have opened 
up possibilities to create strongly correlated states of matter with sizable 
electromagnetic or photonic components. Enabled by strong atom-photon 
coupling on the single-quantum level, for example in cavity QED and with 
Rydberg atoms, it is now possible to study the statistical, and generically 
far-from-equilibrium, physics of photons in new regimes far beyond 
what is know from the laser theory developed in the 1970's. Here, I will 
survey our first attempts to classify such phases of photonic matter into 
universality classes including glasses, superradiant Fermi gases, and 
attractive quantum liquids.
In the second part, I will consider electronic materials in which 
frustration and interactions are so strong that, collective excitations 
made out of electronic spins behave as emergent photons, and compute 
new observable signatures thereof.
Further information: http://www.thp.uni-koeln.de/~strack/