  We describe a light-pulse atom interferometer that is suitable for any
species of atom and even for electrons and protons as well as their
antiparticles, in particular for testing the Einstein equivalence principle
with antihydrogen. The design obviates the need for resonant lasers through
far-off resonant Bragg beam splitters and makes efficient use of scarce atoms
by magnetic confinement and atom recycling. We expect to reach an initial
accuracy of better than 1% for the acceleration of free fall of antihydrogen,
which can be improved to the part-per million level.
