Critical Combinations of Higher-Order Terms in Einstein-Maxwell Theory and Compactification

الملخص EN

We discuss the role of a particular combination of higher derivative terms in higher dimensional theories, particularly in the background of spontaneous compactification.

Two classes of theories are proposed in this paper.

The first model as a generalization of the critical gravity with the Maxwell field could have a de Sitter solution.

We consider the Lanczos-Lovelock term and Horndeski term as well as the higher-order Maxwell term for the second model, which contains a possible longer expansion time for the inflationary phase.

It is interesting that both models can be regarded as the generalization of the Randjbar-Daemi, Salam and Strathdee (RSS) model and give the well behavior for inflation stage under the specific assumptions.