English

In-In EFT

High Energy Physics - Theory 2025-06-30 v1 High Energy Physics - Phenomenology

Abstract

The effective field theory (EFT) construction when the objects of interest are the In-In (or real time) correlators rather than the In-Out S-matrix elements is constructed. This is done using the formal equivalence between the In-In and In-Out correlation functions, and demanding that the EFT and the full theory provide the same answers for the In-In correlation functions. Matching coefficients for a simple example are provided including for operators with two or more space or time derivatives. It is also pointed out that the Schrodinger representation of QFT captures some of the desired features of these calculations in a natural way and may actually serve as a link between these calculations and the broader amplitude programme.

Keywords

Cite

@article{arxiv.2506.22045,
  title  = {In-In EFT},
  author = {Namit Mahajan},
  journal= {arXiv preprint arXiv:2506.22045},
  year   = {2025}
}

Comments

23 pages

R2 v1 2026-07-01T03:36:04.704Z