  Conceptually different from the decoherence program, we present a novel
theoretical approach to macroscopic realism and classical physics within
quantum theory. It focuses on the limits of observability of quantum effects of
macroscopic objects, i.e., on the required precision of our measurement
apparatuses such that quantum phenomena can still be observed. First, we
demonstrate that for unrestricted measurement accuracy no classical description
is possible for arbitrarily large systems. Then we show for a certain time
evolution that under coarse-grained measurements not only macrorealism but even
the classical Newtonian laws emerge out of the Schroedinger equation and the
projection postulate.
