Quantum many-body problems still remain largely
unsolved because their information content grows exponentially with particle
number due to interactions. I will overview why identifying particle clusters yields
a realistic first-principles description of diverse many-body and
quantum-optics problems, and why it introduces the control of clusters –
clustronics – as a powerful approach to realize macroscopic quantum effects. I
will discuss how clustronics theory can realistically guide experiments by
showing several examples involving semiconductors and atomic Bose-Einstein
condensates.