  We report on a search for extra spatial dimensions compactified at radii that
are vast compared to those of the Planck length, and even larger than the
distance corresponding to the scale of electroweak symmetry breaking. The study
is based on the suggestion that there may be only a single mass scale
appropriate to particle phenomena, this being the effective Planck scale M_S,
which also serves as the scale for electroweak symmetry breaking. The only
results that have been presented thus far from the Tevatron are based on data
for e^+e^- and \gamma\gamma production at D\O, and provide the most restrictive
lower limits to date on M_S of \approx 1 TeV.
