  This work proposes a stringent concept of matter mass generation and Theta
vacuum in the context of local gauge theory for the strong force under the
constraint of the flat universe. The matter mass is generated as the
consequence of dynamical spontaneous symmetry breaking (DSSB) of gauge symmetry
and discrete symmetries, which is motivated by the parameter Theta representing
the surface term. Matter mass generation introduces the typical features of
constituent particle mass, dual Meissner effect, and hyperfine structure. The
Theta term plays important roles on the DSSB of the gauge group and on the
quantization of the matter and vacuum space. The Theta vacuum exhibits the
intrinsic principal number and intrinsic angular momentum for intrinsic space
quantization in analogy with the extrinsic principal number and extrinsic
angular momentum for extrinsic space quantization.
