Searcharxiv⌕ Search

arXiv subjects

Daniel H. T. Franco

Publications and source records attributed to Daniel H. T. Franco.

At least 19 recordsLinked to original sources
arXiv2025

Spin One Matter Fields

It is shown how spin one vector matter fields can be coupled to a Yang-Mills theory. Such matter fields are defined as belonging to a representation $R$ of this Yang-Mills gauge algebra $\mathfrak{g}$. It is also required that these fields together with the original gauge fields be the gauge fields of an embedding total gauge algebra $\mathfrak{g}_{\rm tot}$. The existence of a physically consistent Yang-Mills action for the total algebra is finally required. These conditions are rather restrictive, as shown in some examples: non-trivial solutions may or may not exist depending on the choice of the original algebra $\mathfrak{g}$ and of the representation $R$. Some examples are shown, the case of the initial algebra $\mathfrak{g}$ = $\mathfrak{u}(1)\oplus\mathfrak{su}(2)$ being treated in more detail.

hep-th↗
arXiv2023

On the relation between Dencker's polarization set and the gauge-fixing in electrodynamics

The purpose of this short review, based in part on ideas developed in an article by the author and Fagundes [3], is to emphasize that the gauge-fixing condition, necessary to eliminate the spurious degrees of freedom of the electromagnetic field, is elegantly handled by Dencker's work on the propagation of polarization sets for systems of real principal type.

math-ph↗
arXiv2016

Moduli Structures, Separability of the Kinematic Hilbert Space and Frames in Loop Quantum Gravity

We reassess the problem of separability of the kinematic Hilbert space in loop quantum gravity under a new mathematical point of view. We use the formalism of frames, a tool used in signal analysis, in order to remove the redundancy of the moduli structures in high valence graphs, without resorting to set extension of diffeomorphism group. For this, we introduce a local redundancy which encodes the concentration of frame vectors on the tangent spaces $T_pM$ around points of intersections $p$ of smooth loops $α$ in $\mathbb{R}^{3}$.

gr-qc↗
arXiv2016

Symanzik-Becchi-Rouet-Stora lessons on renormalizable models with broken symmetry: the case of Lorentz violation

In this paper, we revisit the issue intensively studied in recent years on the generation of terms by radiative corrections in models with broken Lorentz symmetry. The algebraic perturbative method of handling the problem of renormalization of the theories with Lorentz symmetry breaking, is used. We hope to make clear the Symanzik's aphorism: "{\it Whether you like it or not, you have to include in the lagrangian all counter terms consistent with locality and power-counting, unless otherwise constrained by Ward identities.}"

hep-th↗
arXiv2013

No one-loop gauge anomalies for a Lorentz-violating quantum electrodynamics: Evaluation of the three-photon vertex

Identification of the diagrams that can lead to gauge anomalies in the (minimal) Lorentz- and $CPT$-violating extension of quantum electrodynamics reveals these are the electron self-energy and vertex correction (related to the Ward-Takahashi identity), the photon self-energy (related to the vacuum polarization tensor transversality), and the three-photon vertex diagrams. All but the latter were explicitly verified to be free of anomalies to first order in loop expansion. Here we provide this remaining evaluation and verify the absence of anomalies in this process.

hep-th↗
arXiv2010

Lorentz and CPT violation in QED revisited: A missing analysis

We investigate the breakdown of Lorentz symmetry in QED by a CPT violating interaction term consisting of the coupling of an axial fermion current with a constant vector field $b$, in the framework of algebraic renormalization -- a regularization-independent method. We show, to all orders in perturbation theory, that a CPT-odd and Lorentz violating Chern-Simons-like term, definitively, is not radiatively induced by the axial coupling of the fermions with the constant vector $b$.

hep-th↗
arXiv2009

Holomorphic Extension Theorem for Tempered Ultrahyperfunctions

In this paper we are concerned with the space of tempered ultrahyperfunctions corresponding to a proper open convex cone. A holomorphic extension theorem (the version of the celebrated edge of the wedge theorem) will be given for this setting. As application, a version is also given of the principle of determination of an analytic function by its values on a non-empty open real set. The paper finishes with the generalization of holomorphic extension theorem à la Martineau.

math.FA↗
arXiv2009

No parity anomaly in massless QED3: a BPHZL approach

In this letter we call into question the perturbatively parity breakdown at 1-loop for the massless QED_3 frequently claimed in the literature. As long as perturbative quantum field theory is concerned, whether a parity anomaly owing to radiative corrections exists or not will be definitely proved by using a renormalization method independent of any regularization scheme. Such a problem has been investigated in the framework of BPHZL renormalization method, by adopting the Lowenstein-Zimmermann subtraction scheme. The 1-loop parity-odd contribution to the vacuum-polarization tensor is explicitly computed in the framework of the BPHZL renormalization method. It is shown that a Chern-Simons term is generated at that order induced through the infrared subtractions -- which violate parity. We show then that, what is called parity anomaly, is in fact a parity-odd counterterm needed for restauring parity.

hep-th↗
arXiv2008

Ultrahyperfunctional Approach to Non-Commutative Quantum Field Theory

In the present paper, we intent to enlarge the axiomatic framework of non-commutative quantum field theories (QFT). We consider QFT on non-commutative spacetimes in terms of the tempered ultrahyperfunctions of Sebastião e Silva corresponding to a convex cone, within the framework formulated by Wightman. Tempered ultrahyperfunctions are representable by means of holomorphic functions. As is well known there are certain advantages to be gained from the representation of distributions in terms of holomorphic functions. In particular, for non-commutative theories the Wightman functions involving the $\star$-product, ${\mathfrak W}^\star_m$, have the same form as the standard form ${\mathfrak W}_m$. We conjecture that the functions ${\mathfrak W}^\star_m$ satisfy a set of properties which actually will characterize a non-commutative QFT in terms of tempered ultrahyperfunctions. In order to support this conjecture, we prove for this setting the validity of some important theorems, of which the CPT theorem and the theorem on the Spin-Statistics connection are the best known. We assume the validity of these theorems for non-commutative QFT in the case of spatial non-commutativity only.

math-ph↗
arXiv2007

A Uniqueness Theorem and Its Application to Field-Theoretical Models with a Fundamental Length

It is shown that if a distribution V of exponential growth has support in a proper convex cone and its Fourier transform is carried by a closed cone different from whole space, then V=0. The application of this result to a {\em quasi-local} quantum field theory (where the fields are localizable only in regions greater than a certain scale of nonlocality) is contemplated. In particular, we show that a number of physically important predictions of {\em local} quantum field theory also hold in a quantum field theory with a fundamental length, as indicated from string theory.

math.FA↗
arXiv2007

Reeh-Schlieder Theorem for Ultrahyperfunctional Wightman Theory

It will be shown that the Reeh-Schlieder property holds for states of quantum fields for ultrahyperfunctional Wightman theory. As by product, it is shown that the Reeh-Schlieder property also holds for states of quantum fields on a non-commutative Minkowski space in the setting ultrahyperfunctional.

math-ph↗
arXiv2006

Paley-Wiener-Schwartz Theorem and Microlocal Analysis in Theory of Tempered Ultrahyperfunctions

We give some precisions on the Fourier-Laplace transform theorem for tempered ultrahyperfunctions introduced by Sebastião e Silva and Hasumi, by considering the theorem in its simplest form: the equivalence between support properties of a distribution in a closed convex cone and the holomorphy of its Fourier-Laplace transform in a suitable tube with conical basis. We establish a generalization of Paley-Wiener-Schwartz theorem for this setting. This theorem is interesting in connection with the microlocal analysis, where a description of the singularity structure of tempered ultrahyperfunctions in terms of the concept of analytic wave front set is given. We also suggest a physical application of the results obtained in the construction and study of field theories with fundamental length.

math-ph↗
arXiv2006

A Note on Superdistributions and Wavefront Set

We present a simple and new method of constructing superdistributions on superspace over a Grassmann-Banach algebra, which close to the de Rham's ``currents'' defined as dual objects to differential forms. The paper also contains the extension of the Hörmander's description of the singularity structure (wavefront set) of a distribution to include the supersymmetric case.

hep-th↗
arXiv2006

A Note on Fourier-Laplace Transform and Analytic Wave front Set in Theory of Tempered Ultrahyperfunctions

In this paper we study the Fourier-Laplace transform of tempered ultrahyperfunctions introduced by Sebastião e Silva and Hasumi. We establish a generalization of Paley-Wiener-Schwartz theorem for this setting. This theorem is interesting in connection with the microlocal analysis. For this reason, the paper also contains a description of the singularity structure of tempered ultrahyperfunctions in terms of the concept of analytic wave front set.

math-ph↗