An article published in the scientific journal Optica describes the development of a new experimental apparatus that explores the boundary between classical and quantum physics, making it possible to simultaneously observe and investigate phenomena peculiar to both worlds. The instrument was developed in Florence and is the result of a collaboration between several research institutions and universities. The device takes advantage of the phenomenon of levitation of nano-objects inside a strongly focused laser beam, that is, the amazing ability of light to "trap" single particles of microscopic size, already observed since the 1980s and perfected, in particular, by U.S. physicist Arthur Ashkin, who was awarded the 2018 Nobel Prize in Physics. The Italian team, led by Francesco Marin (University of Florence and CNR-INO), used this technique to simultaneously trap, by exploiting light beams of different colors, a pair of glass nanospheres: these, inside the optical trap, oscillate around their equilibrium point with very specific frequencies, thus allowing the observation of both "classical" and "quantum" behaviors, the latter often decidedly counter-intuitive.