"Will quantum theory be different in the macro-world?"
Prof. Lajos Diósi
Wigner Research Center for Physics & Eötvös Loránd University (Hungary)

Quantum theory was invented for the microscopic world, and proved accurate there. Is it valid in the macroscopic world as well? Is quantum theory universal from particle physics to cosmology? We might like to think so. Except that the experimental evidences are lacking, the relevant theories limp along, and there are crippling conceptual problems. It is therefore not impossible that quantum theory will be different when it reaches the macro-world. But how different will it be? In quantum theory, the micro-world only affects the macro-world when a measurement is made on the micro-world. Wouldn't there exist certain spontaneous measurements, acting universally everywhere and everytime, negligibly weak in the micro-world and amplified in the macro-world? What does such a theory of spontaneous measurement (i.e., spontaneous wavefunction collapse) look like and what is it good for?