A non-anthropic origin for a small cosmological constant

Abstract

An impressive variety of recent observations which include luminosity evolutions of high red shift supernovae strongly suggest that the cosmological constant (/\)is not zero. Even though the /\-term may dominate cosmic dynamics at the present epoch, such a value for the vacuum energy is actually unnaturally small. The difficulties in finding a suitable explanation (based on fundamental physics) for such a small residual value for the cosmological term has led several authors to resort to an anthropic explantaion for its existence. Here I present a few examples some based on phase transitions in the early universe involving strong or electro weak interactions and other on gravitational spin interactions to show how the cosmical term of the corect observed magnitude can arise from fundamental physics involving gravity.