HOW TO LIMIT RADIATIVE CORRECTIONS TO THE COSMOLOGICAL CONSTANT BY M^4_Susy
Abstract
Supergravity models are constructed in which the effective low energy theory contains only ``super-soft'' explicit supersymmetry breaking: masses of the scalars and pseudoscalars within a multiplet are split in opposite directions. With this form of supersymmetry breaking the radiative corrections of the matter sector to the vacuum energy are bounded by
O(
M
4
Susy
)
to all orders in perturbation theory, and we require
Str
M
2
=0
including the hidden sector. The models are based on Kähler potentials obtained in recent orbifold compactifications, and we describe the construction of realistic theories.