Next Article in Journal
LAMOST J064137.77+045743.8: A Newly Discovered Binary of an A7 Pulsating Subgiant and a Flaring Red Dwarf
Previous Article in Journal
Bayesian Inference of Primordial Magnetic Field Parameters from CMB with Spherical Graph Neural Networks
 
 
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

A Note on the Existence of Equal-Time Correlators

by
Bruno Bucciotti
1,2
1
Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
2
INFN, Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa, Italy
Universe 2026, 12(2), 35; https://doi.org/10.3390/universe12020035
Submission received: 29 December 2025 / Revised: 17 January 2026 / Accepted: 23 January 2026 / Published: 27 January 2026
(This article belongs to the Section Foundations of Quantum Mechanics and Quantum Gravity)

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.
Keywords: cosmological correlators; quantum field theory cosmological correlators; quantum field theory

Share and Cite

MDPI and ACS Style

Bucciotti, B. A Note on the Existence of Equal-Time Correlators. Universe 2026, 12, 35. https://doi.org/10.3390/universe12020035

AMA Style

Bucciotti B. A Note on the Existence of Equal-Time Correlators. Universe. 2026; 12(2):35. https://doi.org/10.3390/universe12020035

Chicago/Turabian Style

Bucciotti, Bruno. 2026. "A Note on the Existence of Equal-Time Correlators" Universe 12, no. 2: 35. https://doi.org/10.3390/universe12020035

APA Style

Bucciotti, B. (2026). A Note on the Existence of Equal-Time Correlators. Universe, 12(2), 35. https://doi.org/10.3390/universe12020035

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop