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Richard Kerner

Publications and source records attributed to Richard Kerner.

At least 19 recordsLinked to original sources
arXiv2026

Connectivity and Rigidity in Borosilicate Glasses

We present a structural analysis of glasses formed by mix of SiO2 and B2O3 glass formers with soda and lime modifiers (Na2O and CaO), which provide a good testing ground for Stochastic Agglomeration Theory. With local structural units properly identified, we can reproduce the one-parameter glass transition temperature T_g (z) curve for the family of (0.75-z) SiO_2 + 0.15 Na_2O + 0.10 CaO + z B_2O_3 glasses studied experimentally by Smedskjaer et al.

cond-mat.dis-nn↗
arXiv2026

Astronomy in the Islamic World: a European Perspective

Mathematical and astronomical achievements of the Islamic World during its golden era are briefly exposed. Thie article is based on the invited talk delivered remotely at the ICRANet-Isfahan Astronomical meeting, November 2-5, 2021, which, in turn, reproduces major parts of one of the chapters of my book ``Our Celestial Clockwork'', published recently (2021) by the World Scientific.

physics.hist-ph↗
arXiv2026

Complex Mass Shells for Coloured quarks and their Asymptotic Confinement

The present paper is the continuation of our previous work (R. Kerner and J. Lukierski, Nuclear Physics B, 2021) where we introduced a Z3-symmetric covering of the Lorentz group as a natural symmetry describing the quark fields. In the current version of QCD quarks are described by coloured triplets of standard Dirac fields. In contrast, we proposed to describe the colour triplets of quarks by entangled Z_3-graded Lee-Wick type fields, one with real mass and the two remaining ones with mutually conjugate complex masses. This is obtained by attributing colour degrees of freedom to six Pauli spinors, three endowed with colours and three with anti-colours, which are united into one 12-component generalized ``coloured Dirac spinor". Thus entangled triplet of quark fields is described on-shell by a linear Schoeodinger-like system akin to the Dirac equation. The sixth-order dispersion relations lead to solutions suitably vanishing in asymptotic region, exhibiting the well established confinement property of coloured quarks' degrees of freedom. We add that in the so modified approach to QCD one should employ in the quark sector the Z3-graded extension of the Lorentz symmetries, which do not commute with hidden SU(3) colour transformations (see Kerner and Lukierski 2021, Kerner 2018}). Propagators and interaction with gluon and electromagnetic fields are discussed in the last section.

hep-ph↗
arXiv2025

A Five-dimensional Kaluza-Klein Approach to Unimodular Gravity

In this article we present a possibility of imposing the unimodular condition within the 5-dimensional Kaluza-Klein theory including the scalar field. Unimodular gravity became an object of increasing interest in the late 80-ties; and was recently used in primordial Universe modeling with cosmological constant, in the context of the Brans-Dicke gravity including scalar field. A generalization of the unimodularity principle to the 5-dimensional Kaluza-Klein model was discussed in our recent paper, in which variational principle is formulated in 5 dimensions first, and dimensional reduction is applied to the resulting set of equations. A cosmological model based on these equations was then presented and discussed. Here we present further developments of this approach, focussing our attention at perturbative aspects and stability of solutions.

gr-qc↗
arXiv2025

On the Stability of Non-Singular Solutions in Effective Theory from Kaluza-Klein Unimodular Gravity

Unimodular theory incorporating the Kaluza-Klein construction in five dimensions leads, after reduction to four dimensions, to a new class of scalar-tensor theory. The vacuum cosmological solutions display a bouncing, non singular behavior. From the four dimensional point of view, the solutions are completely regular. However, the propagation of gravitational waves in this geometry displays the presence of instabilities which reflect some features of the original five dimensional structure. Comparison with a four dimensional quantum model with cosmological constant, which has a similar background behavior, is discussed.

gr-qc↗
arXiv2024

Polar magnetic fields in black-hole space-times

To model magnetic fields of compact objects we solve the Maxwell equations in the background of the exterior static Schwarzschild and slowly rotating Kerr space-times. We impose the boundary condition that the electromagnetic fields are to vanish at infinity. A full set of solutions is obtained, describing axially symmetric magnetic fields, supplemented by axial electric fields in the case of non-vanishing rotation of the gravitational background. We study the motion of charged test particles in these combined gravitational and electromagnetic fields, in particular considering the conditions for circular equatorial orbits. Such orbits always exist in odd-multipole magnetic fields, and they can exist for particular radii in a combination of two or more even-multipole magnetic fields. Combinations of several odd-multipole fields can give rise to radial variation in the field orientation and the direction of motion of charged particles. Deviations from circularity are described using a perturbative approach. This also allows to study the stability of the parent circular orbits.

gr-qc↗
arXiv2024

A unimodular Kaluza-Klein theory

Unimodular gravity became an object of increasing interest in the late $80$-ties and was recently used in primordial Universe modeling with cosmological constant, in the context of the Brans-Dicke gravity including scalar field. In the present article we investigate the possibility of imposing the unimodular condition within the $5$-dimensional Kaluza-Klein theory including the scalar field. The variational principle is formulated in $5$ dimensions first, and dimensional reduction is applied to the resulting set of equations. A cosmological model based on these equations is then presented and discussed.

gr-qc↗
arXiv2023

Non-linear Electrodynamics derived from the Kaluza-Klein Theory

The lagrangian of the Kaluza-Klein theory, in its simplest five-dimensional version, should include not only the scalar curvature R, but also the quadratic Gauss-Bonnet invariant. The general lagrangian is computed and the resulting non-linear equations which generalize Maxwell's system in a quite unique way are investigated. The possibility of the existence of static solutions is presented, and the qualitative behaviour of such solutions is discussed.

math-ph↗
arXiv2022

Evolution of Local Structures in Alkali-Borate Glasses

We analyze the dependence of relative proportion of various characteristic clusters in binary alcali-borate glasses on modifier's concentration $x$. A pure $B_2O_3$ glass contains a huge amount of boroxol rings and some amount of boron atoms in between, linking the boroxol rings via oxygen bonds. The addition of the $Na_2O$ modifier creates four-coordinated borons, but the resulting network glass remains totally connected. We study local transformations that lead to creation of new configurations like tetraborates, pentaborates, diborates, etc., and set forth a non-linear differential system similar to the Lotka-Volterra model. The resulting density curves of various local confugurations as functions of $x$ are obtained. Then the average rigidity is evaluated, enabling us to compute the glass transition temperature $T_g(x)$ for a given value of $x$

cond-mat.dis-nn↗
arXiv2022

Brans-Dicke unimodular gravity

We propose a unimodular version of the Brans-Dicke theory designed with a constrained Lagrangian formulation. The resulting field equations are traceless. The vacuum solutions in the cosmological background reproduce the corresponding solutions of the usual Brans-Dicke theory but with a cosmological constant term. A perturbative analysis of the scalar modes is performed and stable and unstable configurations appear in contrast with the Brans-Dicke case for which only stable configurations occur. On the other hand, tensorial modes in this theory remains the same as in the traditional Brans-Dicke theory.

gr-qc↗
arXiv2022

Ternary generalization of Heisenberg's Algebra

A concise study of ternary and cubic algebras with $Z_3$ grading is presented. We discuss some underlying ideas leading to the conclusion that the discrete symmetry group of permutations of three objects, $S_3$, and its abelian subgroup $Z_3$ may play an important role in quantum physics. We show then how most of important algebras with $Z_2$ grading can be generalized with ternary composition laws combined with a $Z_3$ grading. We investigate in particular a ternary, $Z_3$-graded generalization of the Heisenberg algebra. It turns out that introducing a non-trivial cubic root of unity, $j = e^{\frac{2 πi}{3}}$, one can define two types of creation operators instead of one, accompanying the usual annihilation operator. The two creation operators are non-hermitian, but they are mutually conjugate. Together, the three operators form a ternary algebra, and some of their cubic combinations generate the usual Heisenberg algebra. An analogue of Hamiltonian operator is constructed by analogy with the usual harmonic oscillator, and some properties of its eigenfunctions are briefly discussed.

math-ph↗
arXiv2021

Internal quark symmetries and colour SU(3) entangled with Z_3-graded Lorentz algebra

In the current version of QCD the quarks are described by ordinary Dirac fields, organized in the following internal symmetry multiplets: the $SU(3)$ colour, the $SU(2)$ flavour, and broken $SU(3)$ providing the family triplets. \noindent In this paper we argue that internal and external (i.e. space-time) symmetries are entangled at least in the colour sector in order to introduce the spinorial quark fields in a way providing all the internal quark's degrees of freedom which do appear in the Standard Model. Because the $SU(3)$ colour algebra is endowed with natural $Z_3$-graded discrete automorphisms, in order to introduce entanglement the $Z_3$-graded version of Lorentz and Poincaré algebras with their realizations are considered. The colour multiplets of quarks are described by $12$-component colour Dirac equations, with a $Z_3$-graded triplet of masses (one real and a Lee-Wick complex conjugate pair). We argue that all quarks in the Standard Model can be described by the $72$-component master quark sextet of $12$-component coloured Dirac fields.

hep-th↗
arXiv2019

Towards a $Z_3$-graded approach to quarks' symmetries

Colour $SU(3)$ group is an exact symmetry of Quantum Chromodynamics, which describes strong interactions between quarks and gluons. Supplemented by two internal symmetries, $SU(2)$ and $U(1)$, it serves as the internal symmetry of the Standard Model, describing as well the electroweak interactions of quarks and leptons. The colour$SU(3)$ symmetry is exact, while two other symmetries are broken by means of the Higgs-Kibble mechanism. The three colours and fractional quarks charges with values $1/3$ and $2/3$ suggest that the cyclic group $Z_3$ may play a crucial role in quark field dynamics. In this paper we consequently apply the $Z_3$ symmetry to field multiplets describing colour quark fields. Generalized Dirac equation for coloured $12$-component spinors is introduced and its properties are discussed. Imposing $Z_3$-graded Lorentz and Poincaré covariance leads to enlargement of quark fields multiplets and incorporates additional $Z_2 \times Z_3$ symmetry which leads to the appearance of three generations (families) of distinct quark doublets.

hep-th↗
arXiv2019

The Z3-graded extension of the Poincaré algebra

A Z3 symmetric generalization of the Dirac equation was proposed in recent series of papers, where its properties and solutions discussed. The generalized Dirac operator acts on "coloured spinors" composed out of six Pauli spinors, describing three colours and particle-antiparticle degrees of freedom characterizing a single quark state, thus combining Z2 x Z_2 x Z_3 symmetries of 12-component generalized wave functions. Spinorial representation of the Z3-graded generalized Lorentz algebra was introduced, leading to the appearance of extra Z2 x Z2 x Z3 symmetries, probably englobing the symmetries of isospin, flavors and families. The present article proposes a construction of Z3-graded extension of the Poincaré algebra. It turns out that such a generalization requires introduction of extended 12-dimensional Minkowskian space-time containing the usual 4-dimensional space-time as a subspace, and two other mutually conjugate "replicas" with complex-valued vectors and metric tensors. Representation in terms of differential operators and generalized Casimir operators are introduced and their symmetry properties are briefly discussed.

physics.gen-ph↗
arXiv2019

Z_3 - graded colour Dirac equations for quarks, confinement and generalized Lorentz symmetries

We propose a modification of standard QCD description of the colour triplet of quarks describing quark fields endowed with colour degree of freedom by introducing a 12-component colour generalization of Dirac spinor, with built-in Z_3 grading playing an important algebraic role in quark confinement. In "colour Dirac equations" the SU(3) colour symmetry is entangled with the Z_3-graded generalization of Lorentz symmetry, containing three 6-parameter sectors related by Z_3 maps. The generalized Lorentz covariance requires simultaneous presence of 24 colour Dirac multiplets, which lead to the description of all internal symmetries of quarks: besides SU(3) \times SU(2) \times U(1), the flavour symmetries and three quark families.

hep-th↗
arXiv2017

Ternary generalization of Pauli's principle and the Z6-graded algebras

We show how the discrete symmetries $Z_2$ and $Z_3$ combined with the superposition principle result in the $SL(2, {\bf C})$-symmetry of quantum states. The role of Pauli's exclusion principle in the derivation of the SL(2, C) symmetry is put forward as the source of the macroscopically observed Lorentz symmetry, then it is generalized for the case of the Z3 grading replacing the usual Z2 grading, leading to ternary commutation relations. We discuss the cubic and ternary generalizations of Grassmann algebra. Invariant cubic forms are introduced, and their symmetry group is shown to be the $SL(2,C)$ group The wave equation generalizing the Dirac operator to the Z3-graded case is constructed. Its diagonalization leads to a sixth-order equation. The solutions cannot propagate because their exponents always contain non-oscillating real damping factor. We show how certain cubic products can propagate nevertheless. The model suggests the origin of the color SU(3) symmetry.

physics.gen-ph↗
arXiv2017

Ternary Z2 x Z3 graded algebras and ternary Dirac equation

The wave equation generalizing the Dirac operator to the Z3-graded case is introduced, whose diagonalization leads to a sixth-order equation. It intertwines not only quark and anti-quark state as well as the "u" and "d" quarks, but also the three colors, and is therefore invariant under the product group Z2 x Z2 x Z3. The solutions of this equation cannot propagate because their exponents always contain non-oscillating real damping factor. We show how certain cubic products can propagate nevertheless. The model suggests the origin of the color SU(3) symmetry and of the SU(2) x U(1) that arise automatically in this model, leading to the full bosonic gauge sector of the Standard Model.

physics.gen-ph↗