arXiv subjects

Ioseph L. Buchbinder

Publications and source records attributed to Ioseph L. Buchbinder.

7 recordsLinked to original sources

arXiv2026

On the Renormalization in Conformal Quantum Gravity

One-loop divergences in classically conformal theory in curved spacetime is a nontrivial issue if the theory under consideration possesses gauge invariance. In this case, quantization involves introducing the gauge-fixing term and the action of ghosts, both of which are not conformal. The formal proof of the conformal invariant renormalizability in this situation, including interacting theories, has been given in the paper from 1984 by one of the present authors. Owing to BRST symmetry, the contributions of the gauge-fixing and ghost sectors to the conformal variation of the effective action cancel each other. This cancellation does not hold in the finite part of the one-loop and higher-loops effective action, that results in the anomaly. In this paper, we extend the early results on conformal matter fields in external gravitational field and apply them to conformal quantum gravity, including the case of conformal gravity coupled to other conformal matter fields. The gauge-fixing in the Weyl-squared gravity is more complicated, nevertheless, the proof of the one-loop conformal invariant renormalization using BRST symmetry is possible. As a preliminary to conformal quantum gravity, we also present a detailed general proof of conformal invariant one-loop divergences in the corresponding semiclassical theory.

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arXiv2025

Renormalizable quantum field theory in curved spacetime with external two-form field

We argue that the renormalizability of interacting quantum field theory on the curved-space background with an additional external antisymmetric tensor (two-form) field requires nonminimal interaction of the antisymmetric field with quantum fermions and scalars. The situation is qualitatively similar to the metric and torsion background. In both cases, one can explore the renormalization group running for the parameters of nonminimal interaction and see how this interaction behaves in the UV limit. General considerations are confirmed by the one-loop calculations in the well-known gauge model based on the $SU(2)$ gauge group.

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arXiv2024

On the renormalization of massive vector field theory coupled to scalar in curved space-time

We consider the renormalization of massive vector field interacting with charged scalar field in curved spacetime. Starting with the theory minimally coupled to external gravity and using the formulations with and without Stückelberg fields, we show that the longitudinal mode of vector field is completely decoupled and the remaining theory of transverse vector field is renormalizable by power counting. The formal arguments based on the covariance and power counting indicate that multiplicative renormalizability of the interacting theory may require introducing two non-minimal terms linear in Ricci tensor in the vector sector. Nevertheless, a more detailed analysis shows that these non-minimal terms violate the decoupling of the longitudinal mode and are prohibited. As a verification of general arguments, we derive the one-loop divergences in the minimal massive scalar QED, using Stückelberg procedure and the heat-kernel technique. The theory without non-minimal terms proves one-loop renormalizable and admits the renormalization group equations for all the running parameters in the scalar and vector sectors. One-loop beta functions do not depend on the gauge fixing and can be used to derive the effective potential.

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arXiv2024

Covariant Cubic Interacting Vertices for Massless and Massive Integer Higher Spin Fields

We develop the BRST approach to construct the general off-shell local Lorentz covariant cubic interaction vertices for irreducible massless and massive higher spin fields on $d$-dimensional Minkowski space. We consider two different cases for interacting higher spin fields: with one massive and two massless; with two massive both with coinciding and with different masses and one massless fields of spins $s_1, s_2, s_3$. Unlike the previous results on cubic vertices we extend our earlier result in [arXiv:2105.12030[hep-th]] for massless fields and employ the complete BRST operator, including the trace constraints that is used to formulate an irreducible representation with definite integer spin. We generalize the cubic vertices proposed for reducible higher spin fields in [arXiv:1205.3131 [hep-th]] in the form of multiplicative and non-multiplicative BRST-closed constituents and calculate the new contributions to the vertex, which contain additional terms with a smaller number space-time derivatives of the fields. We prove that without traceless conditions for the cubic vertices in [arXiv:1205.3131 [hep-th]] it is impossible to provide the noncontradictory Lagrangian dynamics and find explicit traceless solution for these vertices. As the examples, we explicitly construct the interacting Lagrangian for the massive of spin $s$ field and massless scalars both with and without auxiliary fields. The interacting models with different combinations of triples higher spin fields: massive of spin $s$ with massless scalar and vector fields and with two vector fields; massless of helicity $λ$ with massless scalar and massive vector fields; two massive fields of spins $s, 0$ and massless scalar are also considered.

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arXiv2017

Massive vector field on curved background: non-minimal coupling, quantization and divergences

We study the effective action for the massive vector field theory non-minimally coupled to external gravitational field. Such a theory is an interesting model both from the theoretical side and also due to the various phenomenological applications to cosmology and astrophysics. The present work pretends to initiate a systematic study of its properties at the quantum level, by exploring free massive vector coupled to an external symmetric second-rank tensor. Stueckelberg scalar field is used to restore the gauge invariance. After that, by using a special gauge fixing and non-local in external fields change of variables, we diagonalize the bilinear form of the action and develop a consistent procedure to study the effective action. As a result we derive a complete non-linear structure of divergences of the effective action and discuss its properties.

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arXiv2012

One-loop divergences in massive gravity theory

The one-loop divergences are calculated for the recently proposed ghost-free version of massive gravity, where the action depends on both metric and external tensor field f. The non-polynomial structure of the massive term is reduced to a more standard form by means of auxiliary tensor field, which is settled on-shell after quantum calculations are performed. As one should expect, the counterterms do not reproduce the form of the classical action. Moreover, the result has the form of the power series in f.

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arXiv1997

On the D = 4, N = 2 Non-Renormalization Theorem

Using the harmonic superspace background field formulation for general D=4, N=2 super Yang-Mills theories, with matter hypermultiplets in arbitrary representations of the gauge group, we present the first rigorous proof of the N=2 non-renormalization theorem; specifically, the absence of ultraviolet divergences beyond the one-loop level. Another simple consequence of the background field formulation is the absence of the leading non-holomorphic correction to the low-energy effective action at two loops.

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