We discuss exact quantization of gravitational fluctuations in the half-BPS sector around AdS5 × S5 background, using the dual super Yang-Mills theory. For this purpose we employ the recently developed techniques for exact bosonization of a finite number N of fermions in terms of N bosonic oscillators. An exact computation of the three-point correlation function of gravitons for finite N shows that they become strongly coupled at sufficiently high energies, with an interaction that grows exponentially in N. We show that even at such high energies a description of the bulk physics in terms of weakly interacting particles can be constructed. The single particle states providing such a description are created by our bosonic oscillators or equivalently these are the multi-graviton states corresponding to the so-called Schur polynomials. Both represent single giant graviton states in the bulk. Multi-particle states corresponding to multi-giant gravitons are, however, different, since interactions among our bosons vanish identically, while the Schur polynomials are weakly interacting at high enough energies.