From inflation to a zero cosmological constant phase without fine tuning

TL;DR

This paper proposes a model where inflation and the cosmological constant problem are addressed simultaneously, using a four-index field strength condensate and a conformal transformation to achieve a zero effective cosmological constant without fine tuning.

Contribution

It introduces a new mechanism where inflation is driven by a condensate of a four-index field strength, leading to a zero cosmological constant independently of the scalar potential.

Findings

Inflation can be driven by a four-index field strength condensate.

The effective scalar potential $V_{eff}$ has a zero minimum without fine tuning.

Reheating after inflation is possible through oscillations around the minimum.

Abstract

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.