  This paper discovers geometric unification theory of the grand unification
and gravitational interactions and their new physics according to the general
fiber bundle theory, symmetry and so on. Consequently, the research of this
paper is based on the exact scientific bases of mathematics and physics. The
Lagrangians of the grand unification and gravitational interactions are
unifiedly deduced from quantitative causal principle (QCP) and satisfy the
gauge invariant principle of general gauge fields interacting with Fermion
and/or boson fields. The geometry and physics meanings of gauge invariant
property of different physical systems are revealed, and it is discovered that
all the Lagrangians of the four fundamental physics interactions are composed
of the invariant quantities in corresponding spacetime structures. The
difficulties that fundamental physics interactions and Noether theorem are not
able to be unifiedly given and investigated are overcome, the geometric
unification theory and origins of the four fundamental physics interactions and
Noether theorem are shown by QCP, their two-order general Euler-Lagrange
Equations and corresponding Noether conservation currents are derived in
general curved spacetime. This paper further deduces QCP from symmetric
principle. Consequently, geometric unification theory of the grand unification
and gravitation theories and Noether theorem based on symmetric principle and
the new physics are given in this paper. This paper further gives the
unification of QCP and symmetric principle. Thus, this paper opens a door to
both study and give new developments of geometric unification theory of physics
laws, and using the new geometric unification theory, a lot of research works
about different branches of physics can be anew done and expressed simpler with
different symmetric characters.
