SearcharxivSearch

arXiv subjects

Spyros Konitopoulos

Publications and source records attributed to Spyros Konitopoulos.

11 recordsLinked to original sources

Tensor extension of the Abelian-Higgs model for a superconductor

We extend the Abelian-Higgs model of superconductivity to incorporate higher-spin particles. Microscopically, these higher-spin states can be modeled as multi-electron clusters, such as spin-1 Copper pairs or quartets, existing alongside the standard Cooper pairs predicted by BCS theory. To account for these composites, we introduce vector and higher-rank tensor non-gauge fields into the Lagrangian, which serve as sources for higher-rank tensor gauge fields. In this work, we extend the particle spectrum by one rank (including the necessary auxiliary fields) and examine the resulting modifications to the fundamental phenomenological parameters of superconductivity, specifically the penetration depth and the correlation length.

hep-th

Unification of Gravity and Internal Interactions

In the gauge theoretic approach of gravity, General Relativity is described by gauging the symmetry of the tangent manifold in four dimensions. Usually the dimension of the tangent space is considered to be equal to the dimension of the curved manifold. However, the tangent group of a manifold of dimension $d$ is not necessarily $SO_d$. It has been suggested earlier that by gauging an enlarged symmetry of the tangent space in four dimensions one could unify gravity with internal interactions. Here we consider such a unified model by gauging the $SO_{(1,17)}$ as the extended Lorentz group overcoming in this way some difficulties of the previous attempts of similar unification and eventually we obtain the $SO_{10}$ GUT, supplemented by an $SU_2 \times SU_2$ global symmetry.

hep-th

Dark Gravitational Sectors on a Generalized Scalar-Tensor Vector Bundle Model and Cosmological Applications

In this work we present the foundations of generalized scalar-tensor theories arising from vector bundle constructions, and we study the kinematic, dynamical and cosmological consequences. In particular, over a pseudo-Riemannian space-time base manifold, we define a fiber structure with two scalar fields. The resulting space is a 6-dimensional vector bundle endowed with a non-linear connection. We provide the form of the geodesics and the Raychaudhuri and general field equations, both in Palatini and metrical method. When applied at a cosmological framework, this novel geometrical structure induces extra terms in the modified Friedmann equations, leading to the appearance of an effective dark energy sector, as well as of an interaction of the dark mater sector with the metric. We show that we can obtain the standard thermal history of the universe, with the sequence of matter and dark-energy epochs, and furthermore the effective dark-energy equation-of-state parameter can lie in the quintessence or phantom regimes, or exhibit the phantom-divide crossing.

gr-qc

Closed Algebras for Higher Rank, non-Abelian Tensor Gauge Fields

A systematic method is presented for the construction and classification of algebras of gauge transformations for arbitrary high rank tensor gauge fields. For every tensor gauge field of a given rank, the gauge transformation will be stated, in a generic way, via an ansatz that contains all the possible terms, with arbitrary coefficients and the maximum number of tensor gauge functions. The requirement for the closure of the algebra will prove to be restrictive, but, nevertheless, leave a variety of choices. Properly adjusting the values of the initial coefficients and imposing restrictions on the gauge functions, one can, one the one hand, recover all the, so far, analysed algebras and on the other, construct new ones. The presentation of a brand new algebra for tensor gauge transformations is the central result of this article.

hep-th

A Priori Tests for the MIXMAX Random Number Generator

We define two a priori tests of pseudo-random number generators for the class of linear matrix-recursions. The first desirable property of a random number generator is the smallness of serial or lagged correlations between generated numbers. For the particular matrix generator called MIXMAX, we find that the serial correlation actually vanishes. Next, we define a more sophisticated measure of correlation, which is a multiple correlator between elements of the generated vectors. The lowest order non-vanishing correlator is a four-element correlator and is non-zero for lag $s=1$. At lag $s \ge 2$, this correlator again vanishes. For lag $s=2$, the lowest non-zero correlator is a six-element correlator. The second desirable property for a linear generator is the favorable structure of the lattice which typically appears in dimensions higher than the dimension of the phase space of the generator, as discovered by Marsaglia. We define an appropriate generalization of the notion of the spectral index for LCG which is a measure of goodness of this lattice to the matrix generators such as MIXMAX and find that the spectral index is independent of the size of the matrix N and is equal to $\sqrt{3}$.

physics.data-an

Proton Spin and Tensorgluons

Recently it was suggested that inside the hadrons there are additional partons - tensorgluons - which carry the same charges as the gluons, but have larger spin. The nonzero density of tensorgluons can be created inside a nucleon by radiation of tensorgluons by gluons. Tensorgluons can carry a part of nucleon momentum together with gluons. Because tensorgluons have a larger spin, they can influence the spin structure of the nucleon. We analyse a possible contribution of polarised tensorgluon density to the spin of the nucleon. This contribution appears in the next to leading order, compared to the gluons and can provide a substantial screening effect due to the larger spin of tensorgluons.

hep-ph

Extension of Chern-Simons forms

We investigate metric independent, gauge invariant and closed forms in the generalized YM theory. These forms are polynomial on the corresponding fields strength tensors - curvature forms and are analogous to the Pontryagin-Chern densities in the YM gauge theory. The corresponding secondary characteristic classes have been expressed in integral form in analogy with the Chern-Simons form. Because they are not unique, the secondary forms can be dramatically simplified by the addition of properly chosen differentials of one-step-lower-order forms. Their gauge variation can also be found yielding the potential anomalies in the gauge field theory.

hep-th

Production of charged spin-two gauge bosons in gluon-gluon scattering

We consider the production of charged spin-two gauge bosons in the gluon-gluon scattering and calculate polarized cross sections for each set of helicity orientations of initial and final particles. The angular dependence of this cross section is compared with the gluon-gluon scattering cross section in QCD .

hep-th

Production of Spin-Two Gauge Bosons

We considered spin-two gauge boson production in the fermion pair annihilation process and calculated the polarized cross sections for each set of helicity orientations of initial and final particles. The angular dependence of these cross sections is compared with the similar annihilation cross sections in QED with two photons in the final state, with two gluons in QCD and W-pair in Electroweak theory.

hep-th

Tensor gauge boson production in high energy collisions

We calculated the leading-order cross section for the helicity two tensor gauge bosons production in fermion pair annihilation process. We compare this cross section with a similar annihilation processes in QED with two photons in the final state and with two gluons in QCD.

hep-th

Propagating modes of non-Abelian tensor gauge field of second rank

In the recently proposed extension of the YM theory, non-Abelian tensor gauge field of the second rank is represented by a general tensor whose symmetric part describes the propagation of charged gauge boson of helicity two and its antisymmetric part - the helicity zero charged gauge boson. On the non-interacting level these polarizations are similar to the polarizations of the graviton and of the Abelian antisymmetric B field, but the interaction of these gauge bosons carrying non-commutative internal charges cannot be directly identified with the interaction of gravitons or B field. Our intention here is to illustrate this result from different perspectives which would include Bianchi identity for the corresponding field strength tensor and the analysis of the second-order partial differential equation which describes in this theory the propagation of non-Abelian tensor gauge field of the second rank.

hep-th