NUMERICAL STUDY OF INDUCED FALSE VACUUM DECAY AT HIGH-ENERGIES

We calculate numerically the probability exp[1/lambda F(E/E(sph), N/N- sph)] of the false vacuum decay in the massive four-dimensional -lambd a phi(4) from multiparticle initial states with fixed number of partic les N whose total energy E is of order or greater than the height of t he barrier E(sph). We find that at E less than or similar to 3E(sph) a nd N less than or similar to 0.4N(sph) the decay is classically forbid den and thus is exponentially suppressed. We argue that the classicall y forbidden region extends, at small N, at least up to E similar to 10 E(sph) and, most likely, to all energies. Our data suggest that the fa lse vacuum decay induced by two-particle collisions is exponentially s uppressed at all energies.