The following work demonstrates the viability of Poincare symmetry in a discrete universe. We develop the technology of the discrete principal Poincare bundle to describe the pairing of (1) a hypercubic lattice `base manifold labeled by integer vertices-denoted ${mathbf{n}}={(n_t,n_x,n_y,n_z)}$-with (2) a Poincare structure group. We develop lattice 5-vector theory, which describes a non-unitary representation of the Poincare group whose dynamics and gauge transformations on the lattice closely resemble those of a scalar field in spacetime. We demonstrate that such a theory generates discrete dynamics with the complete infinitesimal symmetry-and associated invariants-of the Poincare group. Following our companion paper, we `lift the Poincare gauge symmetries to act only on vertical matter and solder fields, and recast `spacetime data--stored in the $partial_muphi(x)$ kinetic terms of a free scalar field theory--as `matter field data-stored in the $phi^mu[mathbf{n}]$ components of the 5-vector field itself. We gauge 5-vector theory to describe a lattice gauge theory of gravity, and discuss the physical implications of a discrete, Poincare-invariant theory.
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