  Based on Haldane's spherical geometrical formalism of two-dimensional quantum
Hall fluids, the relation between the noncommutative geometry of $S^2$ and the
two-dimensional quantum Hall fluids is exhibited. If the number of particles
$N$ is infinitely large, two-dimensional quantum Hall physics can be precisely
described in terms of the noncommutative U(1) Chern-Simons theory proposed by
Susskind, like in the case of plane. However, for the finite number of
particles on two-sphere, the matrix-regularized version of noncommutative U(1)
Chern-Simons theory involves in spinor oscillators. We establish explicitly
such a finite matrix model on two-sphere as an effective description of
fractional quantum Hall fluids of finite extent. The complete sets of physical
quantum states of this matrix model are determined, and the properties of
quantum Hall fluids related to them are discussed. We also describe how the
low-lying excitations are constructed in terms of quasiparticle and quasihole
excitations in the matrix model. It is shown that there consistently exists a
Haldane's hierarchical structure of two-dimensional quantum Hall fluid states
in the matrix model. These hierarchical fluid states are generated by the
parent fluid state for particles by condensing the quasiparticle and quasihole
excitations level by level, without any requirement of modifications of the
matrix model.
