  A hyperunified field theory is built in detail based on the postulates of
gauge invariance and coordinate independence along with the conformal scaling
symmetry. All elementary particles are merged into a single hyper-spinor field
and all basic forces are unified into a fundamental interaction governed by the
hyper-spin gauge symmetry SP(1,$D_h$-1). The dimension $D_h$ of hyper-spacetime
is conjectured to have a physical origin in correlation with the hyper-spin
charge of elementary particles. The hyper-gravifield fiber bundle structure of
biframe hyper-spacetime appears naturally with the globally flat Minkowski
hyper-spacetime as a base spacetime and the locally flat hyper-gravifield
spacetime as a fiber that is viewed as a dynamically emerged hyper-spacetime
characterized by a non-commutative geometry. The gravitational origin of gauge
symmetry is revealed with the hyper-gravifield that plays an essential role as
a Goldstone-like field. The gauge-gravity and gravity-geometry correspondences
bring about the gravitational gauge-geometry duality. The basic properties of
hyperunified field theory and the issue on the fundamental scale are analyzed
within the framework of quantum field theory, which allows us to describe the
laws of nature in deriving the gauge gravitational equation with the conserved
current and the geometric gravitational equations of Einstein-like type and
beyond.
