Consequences of Inhomogeneous Inflation on the primordial gravitational wave background

Inflation doesn't always begin generically as it is now well known that whether inflation can begin depends on both the initial conditions which can be highly inhomogeneous and its dynamical model. We show that, by making some broad assumptions about the initial conditions, one can put a bound on the scalar-tensor ratio r, which is a key target of any next generation CMB experiment such as CMB-S4.