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Physicist, University of Vienna; Scientific Director, Institute of Quantum Optics and Quantum Information; President, Austrian Academy of Sciences; Author, Dance of the Photons: From Einstein to Quantum Teleportation

What I believe but cannot prove is that quantum physics teaches us to abandon the distinction between information and reality.

The fundamental reason why I believe in this is that it is impossible to make an operational distinction between reality and information. In other words, whenever we make any statement about the world, about any object, about any feature of any object, we always make statements about the information we have. And, whenever we make scientific predictions we make statements about information we possibly attain in the future. So one might be tempted to believe that everything is just information. The danger there is solipsism and subjectivism. But we know, even as we cannot prove it, that there is reality out there. For me the strongest argument for a reality independent of us is the randomness of the individual quantum event, like the decay of a radioactive atom. There is no hidden reason why a given atom decays at the very instant it does so.

So if reality exists and if we will never be able to make an operational distinction between reality and information, the hypothesis suggests itself that reality and information are the same. We need a new concept which encompasses both. In a sense, reality and information are the two sides of the same coin.

I feel that this is the message of the quantum. It is the natural extension of the Copenhagen interpretation. Once you adopt the notion that reality and information are the same all quantum paradoxes and puzzles disappear, like the measurement problem or Schrödinger's cat. Yet the price to pay is high. If my hypothesis is true, many questions become meaningless. There is no sense then to ask, what is "really" going on out there. Schrödinger's cat is neither dead nor alive unless we obtain information about her state.

By the way, I also believe that some day all computers will be quantum computers. The reason I believe this is the ongoing miniaturization of electronic components. And, certainly, we will learn to overcome decoherence. We will learn how to observe quantum phenomena outside the shielded environment of laboratories. I hope I will still be alive when this happens.