Computing c - and a -functions from entanglement
Year: 2026
Type: article
Abstract: We investigate the connection between entanglement entropy and the notion of irreversibility in the renormalization-group flow in the context of a simple theory for which an explicit calculation from first principles is feasible. The change of the entanglement entropy for a spherical entangling surface as its radius grows from zero to infinity corresponds to the flow from the UV to the IR. Through analytical and numerical means, we compute the entanglement entropy for a free massive scalar theory, making use of the method of correlation functions. We deduce a c -function in 1 + 1 dimensions and an a -function in 3 + 1 dimensions. Both functions are monotonic and vary continuously between one and zero, which are the expected values for this theory.
DOI: 10.1103/knz5-m5zq
Institution: National and Kapodistrian University of Athens
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
OpenAlex ID: W4417413558