Scalar–tensor gravity and Aharonov–Bohm electrodynamics with bosons: applications to superconductors

F. Minotti; G. Modanese

doi:10.1140/epjc/s10052-026-15825-7

EPJ

a
b
c
d
e
ap
st
h
plus
ds
pv
ti
qt
am
n
ri

2024 Impact factor 4.8

Particles and Fields

Open Access

Eur. Phys. J. C (2026) 86: 593
https://doi.org/10.1140/epjc/s10052-026-15825-7

Regular Article - Theoretical Physics

Scalar–tensor gravity and Aharonov–Bohm electrodynamics with bosons: applications to superconductors

F. Minotti¹^,2 and G. Modanese³^a

¹ Departamento de Física, Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Buenos Aires, Argentina
² Instituto de Física Interdisciplinaria y Aplicada (INFINA), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
³ Free University of Bozen-Bolzano, Faculty of Engineering, 39100, Bolzano, Italy

^a This email address is being protected from spambots. You need JavaScript enabled to view it.

Received: 27 March 2026
Accepted: 9 May 2026
Published online: 1 June 2026

Abstract

We study a scalar–tensor extension of gravity with two scalar fields coupled to the Aharonov–Bohm extension of electrodynamics, where the scalar mode $S \equiv \partial_{μ} A^{μ}$ $Mathematical equation: $$S\equiv \partial _\mu A^\mu $$$ is dynamical. In this framework the trace of the electromagnetic energy–momentum tensor is nonvanishing and the scalar S induces an electro-gravitational coupling that can be enhanced by the vacuum expectation value of the second gravitational scalar. For bosonic matter described by a macroscopic wavefunction (as in superconductors), the coupling to the electromagnetic potential generates S already at the semiclassical level, implying sizable junction-induced discontinuities. Including the scalar–tensor sector yields a nonlinear system for S and a gravitational scalar combination $β$ $Mathematical equation: $$\beta $$$ that admits a bulk saturation solution $S_{sat}^{2} = {(Λ λ_{L}^{2})}^{- 1}$ $Mathematical equation: $$S_\textrm{sat}^2=(\Lambda \lambda _L^2)^{-1}$$$ and a corresponding threshold condition for macroscopic effects. We apply these results to pulsed discharges across normal-superconducting junctions and obtain scaling relations for the onset of anomalous gravitational signals in terms of current density, pulse duration, and superconducting volume, consistent with reported threshold behavior in two independent experimental configurations for a single microscopic parameter. We also present time-dependent propagating solutions in the weak-field regime and derive a class of one-dimensional traveling exact solutions of the nonlinear vacuum Einstein equations.

© The Author(s) 2026

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.