  We employ a simple and mostly accurate dimensional interpolation formula
using dimensional limits $D=1$ and $D=\infty$ to obtain $D=3$ ground-state
energy of metallic hydrogen. We also present results describing the phase
transitions for different symmetries of three-dimensional structure lattices.
The interpolation formula not only predicts fairly accurate energies but also
predicts a correct functional form of the energy as a function of the lattice
parameters. That allows us to calculate different physical quantities such as
the bulk modulus, Debye temperature, and critical transition temperature, from
the gradient and the curvature of the energy curve as a function of the lattice
parameters. These theoretical calculations suggest that metallic hydrogen is a
likely candidate for high temperature superconductivity. The dimensional
interpolation formula is robust and might be useful to obtain the energies of
complex many-body systems.
