Signs of the time: Melonic theories over diverse number systems
Steven S. Gubser, Matthew Heydeman, Christian Jepsen, Sarthak Parikh, Ingmar Saberi, Bogdan Stoica, Brian Trundy
TL;DR
The paper extends melonic tensor models to both real and $p$-adic number systems via sign characters, unifying fermionic and bosonic Klebanov–Tarnopolsky constructions under either $O(N)^3$ or $Sp(N)^3$ symmetry. It develops bilocal kinetic terms, analyzes the Schwinger–Dyson equation in the leading melonic limit, and demonstrates universal infrared scaling of the two-point function of the form $G(t)=b\,\mathrm{sgn}(t)/|t|^{1/2}$ across realizations, with the IR amplitude dictated by generalized $\Gamma$-function data of multiplicative characters. For direction-dependent ultrametric signs, the SD equation becomes local and admits an exact quartic-solution interpolation between UV and IR; a Wilsonian non-renormalization perspective explains why the bilocal kinetic term remains undeformed at leading order while the IR physics is controlled by a strongly coupled quartic interaction. The work provides a coherent framework that bridges Archimedean and non-Archimedean melonic theories, highlights the role of sign characters in determining symmetry and statistics, and outlines several directions for extending the analysis to broader $p$-adic extensions and deeper renormalization-group insights.
Abstract
Melonic field theories are defined over the $p$-adic numbers with the help of a sign character. Our construction works over the reals as well as the $p$-adics, and it includes the fermionic and bosonic Klebanov-Tarnopolsky models as special cases; depending on the sign character, the symmetry group of the field theory can be either orthogonal or symplectic. Analysis of the Schwinger-Dyson equation for the two-point function in the leading melonic limit shows that power law scaling behavior in the infrared arises for fermionic theories when the sign character is non-trivial, and for bosonic theories when the sign character is trivial. In certain cases, the Schwinger-Dyson equation can be solved exactly using a quartic polynomial equation, and the solution interpolates between the ultraviolet scaling controlled by the spectral parameter and the universal infrared scaling. As a by-product of our analysis, we see that melonic field theories defined over the real numbers can be modified by replacing the time derivative by a bilocal kinetic term with a continuously variable spectral parameter. The infrared scaling of the resulting two-point function is universal, independent of the spectral parameter of the ultraviolet theory.
