5 papers
Stable Causality and Microcausality for Drummond-Hathrell Photons
Madhukar Deb, Jay Desai, Diptimoy Ghosh
Local superluminal photon propagation arises at in the Drummond Hathrell (DH) effective action obtained by integrating out the electron in QED coupled to gra…
Singularities in Cosmological Loop Correlators II : Non Local Interactions and Flat Space limits
Elaf Ansari, Supritha Bhowmick, Diptimoy Ghosh
Non-local interactions naturally arise in the ADM formalism after solving the constraint equations and substituting their solutions back into the action. However, the effects of th…
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…
Positivity at 1-Loop: Bounds on Photon and Gluon EFTs
Jay Desai, Diptimoy Ghosh
In this paper, we attempt to derive ``positivity" bounds on Photon and Gluon Effective Field Theories (EFTs) at one loop level. While for the Photon case, the one loop amplitude is…
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…