The Four-Body System Made up of Hydrogen and Antihydrogen

 In view of current interest in the trapping of antihydrogen atoms at low temperatures [1–3], we have investigated the reasons for considering that does not have a bound state. We go on to carry out a four-body variational calculation for s-wave hydrogen-antihydrogen scattering, using the Kohn variational method. This is a continuation of earlier work on interactions [5–7]. Received October 30, 2001; accepted for publication November 21, 2001