A Note on the Existence of Equal-Time Correlators
Abstract
We study the conditions under which momentum-space equal-time correlators of scalar fields are finite in flat space. We identify cases where these correlators can be divergent even after renormalization, and we provide sufficient criteria for their existence. Concrete examples are discussed, including the well-known λϕ4 model, composite operators, and effective field theories.
Fields of Study & Subjects
Black Holes and Theoretical Physics
Advanced Mathematical Physics Problems
Quantum Electrodynamics and Casimir Effect
Publication details
- Journal / source
- Universe
- Publisher
- MDPI AG
- Volume
- 12
- Issue
- 2
- Pages
- 35–35
- Publication date
- 27 January 2026
- Language
- EN