Scale, gauge couplings, soft terms and toy compactification in M-theory onS-1/Z(2)

In M-theory on S-1/Z(2), we point out that to he consistent, we should keep the scale, gauge couplings and soft terms at next order, and obtain the so ft term relations M-1/2 = -A, \M-0/M-1/2\ less than or equal to 1/root 3 in the standard embedding, and M-1/2 = -A in the non-standard embedding with five branes and K-5,K-n = 0. We construct a toy compactification model whic h includes higher order terms in the four-dimensional Lagrangian in standar d embedding, and discuss its scale, gauge couplings, soft terms, and show t hat the higher order terms do affect the scale, gauge couplings and especia lly the soft terms if the next order correction was not small. We also cons truct a toy compactification model in non-standard embedding with five bran es and discuss its phenomenology. We argue that one might not push the phys ical Calabi-Yau manifolds volume to zero at any point along the eleventh di mension. (C) 2000 Elsevier Science B.V. All rights reserved.