Blue Isocurvature Perturbations and EFTofLSS based Forecast

In this talk, we will present blue tilted axionic isocurvature spectra and possible constraints/sensitivities from experiments. Firstly, we will discuss the strongly blue tilted (nI~4) isocurvature spectrum generated during inflation for the mass parameter region just when the quantum oscillator modes are starting to be underdamped. Interestingly, there exist parametric regions with a strong resonant spectral behavior that leads to rich isocurvature spectral shapes and large amplitude enhancements. These can be particularly interesting with observational consequences, especially in relation to PBH generation in certain models.  Lastly, we will examine the current 2-sigma evidence from last Planck/BOSS results and forecast constraints/sensitivities for LSS experiments such as Euclid (upcoming) and MegaMapper (proposed) using EFTofLSS based perturbative technique for a better theoretical error control. In the process we will comment upon the consistent renormalization requirements for mixed adiabatic and blue isocurvature primordial initial conditions.