Quantum Reality: From Fundamental Questions to a New Technology

Lay people generally assume that science and physics in particular deals with the question “what is reality?” and is capable in fact of depicting the reality of our world. In particular, most physicists think that quantum physics is the best that science has produced for explaining reality. At the same time, we are offered a situation in which atoms or electrons can be seen as waves, or as particles, and the one picture is inconsistent with the other. Does reality then depend on the experimental setting, namely on the choice of the observer? Such and similar fundamental questions have led to experiments with individual quantum particles. Unexpectedly to all early experimentalists in the filed this kind of work has led to ideas for a new information technology including topics like quantum cryptography, quantum computation, and quantum teleportation. These new experiments again raise new fundamental questions like “What is computation?”