arXiv subjects

R. J. Bueno Rogerio

Publications and source records attributed to R. J. Bueno Rogerio.

At least 19 recordsLinked to original sources

arXiv2025

Spinor Adjoints, Gauge Invariance and a new Road to Sterile Neutrinos

In this work, we analyze the possibilities of certain gauge transformations regarding some specific spinorial dual structures. To this end, we define a general structure, which can be expressed in terms of discrete symmetry operators associated with parity, charge conjugation, and time reversal. To this end, we consider the demand of tensor covariance of the spinor bilinears under space-time transformations and also deep algebraic considerations such as the invertibility of the dual structure which guarantee that the physical information remains unchanged (respecting the Fierz-Pauli-Kofink identities), and so on. Later, we examine the global gauge freedom implicated by each choice of dual and point out the physical implications. The final goal is achieved by establishing a well-defined coupling between the Elko and standard model neutrinos in a prelude for a new formulation of the hypothetical so-called sterile neutrino.

hep-th↗

arXiv2024

On Wigner Degeneracy in Elko theory: Hermiticity and Dark Matter

In this paper, we provide a set of Hermitian interactions for quantum fields based on Elko, considering the recent achievements concerning the most general form of singular spinors and Wigner degeneracy. We consider Hermiticity and renormalizability a criterion to define the derivative Elko-Higgs interaction as the suitable candidate for a dark coupling. Then, the free parameters of the model are fixed by cosmological constraints on the dark matter abundance, bounds on the Higgs invisible decays, and limits on the electron-dark matter scattering mediated by the Higgs.

hep-ph↗

arXiv2024

A note on hidden classes in spinor classification

The Lounesto classification is a well-established scheme for categorizing spinors based on their physical content, which are determined by their associated bilinear forms. It consists of six disjoint classes encompassing the known spinors within the context of the standard model of high-energy physics. However, advancements in theories beyond the standard model have opened the door to potential new spinorial adjoint structures, leading to new unforeseen classess. These developments indicate the potential for extending the standard Lounesto classification. In this paper, we explore all possible subclasses that could extend the Lounesto scheme. We highlight the most relevant subclasses by imposing constraints to their corresponding dual structures, thus broadening our understanding of spinor and its applications in theoretical physics.

math-ph↗

arXiv2024

Singular spinors as expansion coefficients of local spin-half fermionic and bosonic fields: On the two-fold Wigner degeneracy

By scrutinizing the singular sector of the Lounesto spinor classification, we investigate the correct definition of the expansion coefficient functions of local fermionic fields within a fully Lorentz covariant theory. As we can observe, a careful definition of the adjoint structure, directed towards local fields, maps singular spinors into class-2 according to a general spinor classification. Furthermore, we investigate all the necessary mathematical tools for constructing local fermionic and bosonic fields and provide insights into the physical implications for the other singular classes. Besides, we also show that incorporating \emph{Wigner degeneracy} maintains the rotational symmetry formalism working in general.

physics.gen-ph↗

arXiv2023

Revisiting Takahashi's inversion theorem in discrete symmetry-based dual frameworks

The so-called Takahashi's \emph{Inversion Theorem}, the reconstruction of a given spinor based on its bilinear covariants, are re-examined, considering alternative dual structures. In contrast to the classical results, where the Dirac dual structure plays the central role, new duals are built using the discrete symmetries $\mathcal{C}, \mathcal{P}, \mathcal{T}$. Their combinations are also taken into account. Furthermore, the imposition of a new adjoint structure led us also to re-examine the representation of the Clifford algebra basis elements, uncovering new bilinear structures and a new Fierz aggregate. Those results might help construct theories for new beyond standard model fields.

hep-th↗

arXiv2022

Spinorial discrete symmetries and adjoint structures

Extending the investigations about the theory of duals, we analyze duals built up with the aid of discrete symmetry operators. We scrutinize algebraic and physical constraints (encompassing them in a theoretical scope) in order to verify which combination of discrete symmetries may compose a physical and mathematical well-posed spinorial dual. In this scenario, we relate the Lounesto classification with several other spinor classification possibilities, attempting to connect classes and physical constraints. Several possibilities are investigated.

hep-th↗

arXiv2021

Spin-half bosonic classification

In this paper, we define a new spinor classification that encompasses the recently proposed spin-half bosons with mass dimension three-half. As it will be shown, these particles, which are governed by a first-order equation and consequently provide a local theory, belong to a specific subclass of class-2 spinors within the bosonic classification, playing a similar role to Dirac spinors within the Lounesto classification. Such bosonic classification is shown to be closely connected with the usual fermionic Lounesto classification, and thus, evincing a symmetry between Dirac fermions and spin-half bosons.

hep-th↗

arXiv2021

Spinorial structures, discrete symmetries and some consequences

In this paper we discuss fundamental aspects related to the helicity and dynamics of the spin-$1/2$ fermions encompassed within the very well-known Lounesto's classification. More specifically, we investigate how the bi-spinorial structures behave under discrete symmetries, as well as analyse some consequences on the spinors dynamics. In addition, we find an interesting relation between the spinor helicity and the Lounesto spinor classification.

math-ph↗

arXiv2020

Regular spinors and fermionic fields

Bearing in mind the Lounesto spinor classification, we connect the expansion coefficients of well behaved fermionic quantum field, i.e., a local field within a full Lorentz covariant theory, with and only with a given subclass of Type-2 spinors according to Lounesto. We comment on theoretical possibilities as well as physical outputs for the other cases.

hep-th↗

arXiv2020

From Dipole spinors to a new class of mass dimension one fermions

In this letter, we investigate a quite recent new class of spin one-half fermions, namely \emph{Ahluwalia class-7 spinors}, endowed with mass dimensionality $1$ rather than $3/2$, being candidates to describe dark matter. Such spinors, under the Dirac adjoint structure, belongs to the Lounesto's class-6, namely dipole spinors. Up to our knowledge, dipole spinor fields have Weyl spinor fields as their most known representative, nonetheless, here we explore the \emph{dark} counterpart of the dipole spinors, which represents eigenspinors of the chirality operator.

physics.gen-ph↗

arXiv2020

Flag-dipole spinors: On the dual structure derivation and $\mathcal{C}$, $\mathcal{P}$ and $\mathcal{T}$ symmetries

In this manuscript we report the flag-dipole spinors dual structure direct definition and analyze the properties behind the corresponding operator which generates such structure. This particular construction may be interesting for cosmological, phenomenological and mathematical physics applications. In addition, we analyse the behaviour of the flag-dipole spinors under action of discrete symmetries, facing an \emph{unconventional} property encoded on $(\mathcal{CPT})^2$.

math-ph↗

arXiv2020

Subliminal aspects concerning the Lounesto's classification

In the present communication we employ a split programme applied to spinors belonging to the regular and singular sectors of the Lounesto's classification, looking towards to unveil how it can be built or defined upon two spinors arrangement. We separate the spinors into two distinct parts and investigate to which class within the Lounesto's classification each part belong. The machinery here developed open up the possibility to better understand how spinors behave under such classification. As we shall see, the resulting spinor from the arrangement of other spinors (belonging to a distinct class or not) does not necessarily inherit the characteristics of the spinors that compose them, as example, such characteristics stands for the class, dynamic or the encoded physical information.

math-ph↗

arXiv2019

A hint towards mass dimension one Flag-dipole spinors

In this report we advance in exploring further details concerning the formal aspects of the construction of a Flag-dipole spinor. We report a (re-)definition of the dual structure which provide a Lorentz invariant and non-null norm, ensuring a local theory. With the new dual structure at hands, we look towards define relevant physical amounts, e.g., spin sums and quantum field operator. As we will see, the Flag-dipole and the Elko's theory are quite familar. In this vein, it is possible, via a matrix transformation, to write Flag-dipole spinors in terms of Elko spinor, evincing that both spinors are physically related and some physical amounts may be stated as equivalent.

hep-th↗

arXiv2019

Remarks on mass dimension one fermions: The underlying aspects, bilinear forms, Spinor Classification and RIM decomposition

In the present essay we review the underlying physical information behind the first concrete example describing a mass dimension one fermion - namely Elko spinors. We start the program exploring the physical information by evaluating the Elko bilinear forms, both within the proper orthochronous Lorentz subgroup as well as within the VSR theory. As we shall see, such structures do not hold the right observance of the Fierz-Pauli-Kofink quadratic relations. Thus, by the aforementioned reasons, we develop a deformation of the Clifford algebra basis. Such protocol can be accomplished by taking precisely the right Elko dual structure during the construction of the bilinear forms related to these spinors. With the appropriated bilinear forms at hands, we search for a real physical interpretation in order to achieve a deeper understanding of such spinor fields. Aiming an interesting application, we present a relation concerning Elko spinors and the neutrino physics via the Heisenberg non-linear theory by means of a bijective linear map between Elko spinors and the so-called Restricted Inomata-McKinley (RIM) spinors. Thus, we describe some of its properties. Some interesting results concerning the construction of RIM-decomposable spinors emerge from such prescription.

hep-th↗

arXiv2019

Constraints on mapping the Lounesto's Classes

The so-called Lounesto's classification engenders six distinct classes of spinors, divided into two sectors: one composed by regular spinors (single-helicity spinors) and the other composed by singular spinors (comprising dual-helicity spinors). In the present essay we develop a mechanism to fully define the right class within the Lounesto's classification a spinor belongs to, without necessity to evaluate the 16 bilinear forms. The analysis lies in the following criteria: a judicious inspection of the phases factor present in both spinor's components. Thus, the machinery developed here works for both regular and singular spinors. Taking advantage of the present algorithm, we analyse, under certain conditions, the possibility to transmute between the six classes.

physics.gen-ph↗

arXiv2019

On the generalized spinor classification: Beyond the Lounesto's Classification

In this paper we advance into a generalized spinor classification, based on the so-called Lounesto's classification. The program developed here is based on an existing freedom on the spinorial dual structures definition, which, in a certain simple physical and mathematical limit, allows us to recover the usual Lounesto's classification. The protocol to be accomplished here gives full consideration in the understanding of the underlying mathematical structure, in order to satisfy the quadratic algebraic relations known as Fierz-Pauli-Kofink identities, and also to provide physical observables. As we will see, such identities impose a given restriction on the number of possible spinorial classes allowed in the classification. We also expose a mathematical device known as \emph{Clifford's algebra deformation}, which ensures real spinorial densities and holds the Fierz-Pauli-Kofink quadratic relations.

hep-th↗

arXiv2019

Massive spin one-half one particle states for the mass dimension one fermions

We study the conditions under which a non-standard Wigner class concerning discrete symmetries may arise for massive spin one-half states. The mass dimension one fermionic states are shown \textcolor{red}{to} constitute explicit examples. We also show how to conciliate these states with the current criticism due to the Lee and Wick, and Weinberg formulation.

hep-th↗

arXiv2019

Mass dimension one fermions and their gravitational interaction

We investigate in detail the interaction between the spin-${1/2}$ fields endowed with mass dimension one and the graviton. We obtain an interaction vertex that combines the characteristics of scalar-graviton and Dirac's fermion-graviton vertices, due to the scalar-dynamic attribute and the fermionic structure of this field. It is shown that the vertex obtained obeys the Ward-Takahashi identity, ensuring the gauge invariance for this interaction. In the contribution of the mass dimension one fermion to the graviton propagator at one-loop, we found the conditions for the cancellation of the tadpole term by a cosmological counter-term. We calculate the scattering process for arbitrary momentum. For low energies, the result reveals that only the scalar sector present in the vertex contributes to the gravitational potential. Finally, we evaluate the non relativistic limit of the gravitational interaction and obtain an attractive Newtonian potential, as required for a dark matter candidate.

hep-ph↗