22 citations · 78 across the 9 of their papers we have counts for
9 papers
Multi-soft theorems for cosmological correlators: Background wave method for scalars & gravitons
Farman Ullah
Cosmological soft theorems (or consistency relations) provide a powerful probe for the physics of inflation. These relations rely on minimal assumptions and hold very generally. Co…
Massive Exchange and the Sign of the Equilateral Bispectrum
Diptimoy Ghosh, Suvashis Maity, Farman Ullah
We study the inflationary bispectrum generated by the tree-level exchange of a massive hidden-sector scalar during inflation. When the interaction between the inflaton and the hidd…
Singularities in Cosmological Loop Correlators
Supritha Bhowmick, Mang Hei Gordon Lee, Diptimoy Ghosh +1
In this work we perform a systematic study of the singularity structure of inflationary correlations at 1-loop. We explicitly compute a few diagrams and find a pattern emerging in…
Cosmological cutting rules for Bogoliubov initial states: any mass and spin
Diptimoy Ghosh, Farman Ullah
The cosmological optical theorem and the cutting rules are well-known consequences of unitary time evolution in cosmology. The earlier works showed that assuming a Bunch-Davies ini…
Cosmological cutting rules for Bogoliubov initial states
Diptimoy Ghosh, Enrico Pajer, Farman Ullah
The field theoretic wavefunction in cosmological spacetimes has received much attention as a fundamental object underlying the generation of primordial perturbations in our univers…
Bispectrum at 1-loop in the Effective Field Theory of Inflation
Supritha Bhowmick, Diptimoy Ghosh, Farman Ullah
In this paper we compute 1-loop corrections to the bispectrum in the decoupling limit of the Effective Field Theory of Inflation (EFToI). We regulate the divergences by employing d…
Mixed Graviton and Scalar Bispectra in the EFT of Inflation: Soft Limits and Boostless Bootstrap
Diptimoy Ghosh, Kushan Panchal, Farman Ullah
Boostless Bootstrap techniques have been applied by many in the literature to compute pure scalar and graviton correlators. In this paper, we focus primarily on mixed graviton and…
Amplitude's positivity vs. subluminality: Causality and Unitarity Constraints on dimension 6 & 8 Gluonic operators in the SMEFT
Diptimoy Ghosh, Rajat Sharma, Farman Ullah
We derive the causality and unitarity constraints on dimension 6 and dimension 8 Gluon field strength operators in the Standard Model Effective Field Theory (SMEFT). In the first p…
Probing the initial state of inflation: analytical structure of cosmological correlators
Diptimoy Ghosh, Amartya Harsh Singh, Farman Ullah
We study the analytic structure of in-in correlation functions in a deSitter background. The aim of this study is to probe the initial conditions for inflation through the features…