From inflation to a zero cosmological constant phase without fine-tuning

We show that it is possible to obtain inflation and also solve the cosmological constant problem. The theory is invariant under changes of the Lagrangian density L to L+const. Then the constant part of a scalar field potential V cannot be responsible for inflation. However, we show that inflation can be driven by a condensate of a four index field strength. A constraint appears which correlates this condensate to V. After a conformal transformation, the equations are the standard GR equations with an effective scalar field potential V_eff which has generally an absolute minimum V_eff=0 independently of V and without fine tuning. We also show that, after inflation, the usual reheating phase scenario (from oscillations around the absolute minimum) is possible.