Abstract:

In this talk I will discuss the main aspects of the cosmological constant problem and present a mechanism that sequesters the matter loop contributions to the cosmological constant from classical gravity. I will focus on the global nature of the cosmological constant problem and explain why its theoretical value is sensitive to high energy physics. Motivated by these issues, I will show how one can write down a local field theory which only affects the trace of Einstein's field equations in the extreme infra-red. This ensures that only the troublesome loop corrections to the cosmological constant are gravitationally decoupled, with all local gravitational sources unaffected.