18 What are these methods, why are they jointly recognized? The key endeavour in the last century of quantum physics has been the exploration of the coupling between matter and electromagnetic radiation. For a long time, the available experimental techniques were limited to a large number of atoms and a very large number of photons. It was only in thought experiments that one envisioned the manipulation of well-controlled individual quantum systems, dreamed of experimenting with a single atom or a single photon. For instance, Einstein and Bohr once imagined weighing a photon trapped forever in a box, covered by perfect mirrors. These gedankenexperiments and their “ridiculous consequences”, as Schrodinger once stated, played a considerable role in the genesis of quantum physics interpretation. The technical progress made these experiments possible. One can now realize some of the founding fathers' thought experiments. D. Wineland's ion traps and S. Haroche's Cavity Quantum Electrodynamics (CQED) have pioneered this domain, which is now thriving worldwide. The 2012 Nobel prize in physics has been awarded jointly to Serge Haroche (College de France and Ecole Normale Superieure) and David Wineland (National Institute for Standards and Technology, USA) “for ground-breaking experimental methods that enable measuring and manipulation of individual quantum systems”. l Michel Brune1, Jean-Michel Raimond1, Claude Cohen-Tannoudji 1,2 DOI: 10.1051/epn/2012601 l 1 Laboratoire Kastler Brossel, ENS, CNRS, UMPC Paris 6, 24 rue Lhomond, 75005 Paris, France l 2 College de France, 11 place Marcelin Berthelot, 75005 Paris, France Nobel 2012: Trapped ions and photons