scholarly journals A torsional completion of gravity for Dirac matter fields and its applications to neutrino oscillations

2016 ◽  
Vol 31 (03) ◽  
pp. 1650014
Author(s):  
Luca Fabbri ◽  
Stefano Vignolo
Keyword(s):  
Neutrino Oscillations ◽  
Dirac Fields ◽  
Matter Fields ◽  
Dirac Matter

In this paper, we consider the torsional completion of gravitation for an underlying background filled with Dirac fields, applying it to the problem of neutrino oscillations: we discuss the effects of the induced torsional interactions as corrections to the neutrino oscillations mechanism.

scholarly journals WEAKLY-INTERACTING MASSIVE PARTICLES IN TORSIONALLY-GRAVITATING DIRAC THEORY

2013 ◽  
Vol 22 (10) ◽  
pp. 1350071 ◽  
Author(s):  
LUCA FABBRI
Keyword(s):  
Dark Matter ◽  
Weakly Interacting Massive Particles ◽  
Dirac Theory ◽  
Dirac Fields ◽  
Weakly Interacting ◽  
Massive Particles ◽  
Matter Fields ◽  
Dirac Matter

We shall consider the problem of Dark Matter (DM) in torsion gravity with Dirac matter fields; we will consider the fact that if Weakly-Interacting Massive Particles in a bath are allowed to form condensates then torsional effects may be relevant even at galactic scales: we show that torsionally-gravitating Dirac fields have interesting properties for the problem of DM. We discuss consequences.

scholarly journals WEAK FORCES AND NEUTRINO OSCILLATIONS UNDER THE STANDARDS OF HYBRID GRAVITY WITH TORSION

2013 ◽  
Vol 28 (35) ◽  
pp. 1350155 ◽  
Author(s):  
SALVATORE CAPOZZIELLO ◽  
LUCA FABBRI ◽  
STEFANO VIGNOLO
Keyword(s):  
Scalar Field ◽  
Degrees Of Freedom ◽  
Neutrino Oscillations ◽  
Gravitational Theory ◽  
Running Coupling ◽  
Weak Forces ◽  
Matter Fields ◽  
Dirac Matter

We present a unifying approach where weak forces and neutrino oscillations are interpreted under the same standards of torsional hybrid gravity. This gravitational theory mixes metric and metric-affine formalism in presence of torsion and allows to derive an effective scalar field which gives rise to a running coupling for Dirac matter fields. In this picture, two phenomena occurring at different energy scales can be encompassed under the dynamics of such a single scalar field, which represents the further torsional and curvature degrees of freedom.

scholarly journals Torsion-gravity for Dirac fields and their effective phenomenology

2014 ◽  
Vol 29 (26) ◽  
pp. 1450133 ◽  
Author(s):  
Luca Fabbri
Keyword(s):  
New Physics ◽  
Nonlinear Interactions ◽  
Dirac Fields ◽  
Relativistic Approximation ◽  
Fermion Fields ◽  
Matter Fields ◽  
Dirac Matter

We will consider the torsional completion of gravity for a background filled with Dirac matter fields, studying the weak-gravitational non-relativistic approximation, in view of an assessment about their effective phenomenology: we discuss how the torsionally-induced nonlinear interactions among fermion fields in this limit are compatible with all experiments and remarks on the role of torsion to suggest new physics are given.

Gauge Field Theory and Gravitation

2020 ◽  
pp. 93-110
Author(s):  
Daniel Canarutto
Keyword(s):  
Field Theory ◽  
Gravitational Field ◽  
Gauge Field ◽  
Internal Structure ◽  
Arbitrary Spin ◽  
Gauge Field Theory ◽  
Dirac Fields ◽  
Matter Fields ◽  
Dynamical Field ◽  
Soldering Form

The notion of 2-spinor soldering form allows a neat formulation, called the ‘tetrad-affine setting’, of a theory of matter and gauge fields interacting with the gravitational field. The latter is represented by a couple constituted by the soldering form and a 2-spinor connection. This approach is suited to describe matter fields with arbitrary spin and generic further internal structure. In particular one gets an approach to interacting Einstein-Cartan-Maxwell-Dirac fields, in which the only assumption is a complex bundle with 2-dimensional fibers: the needed bundles are obtained from it by natural geometric contructions, and any object which is not determined from these ‘minimal geometric data’ is assumed to be a dynamical field.

scholarly journals Nonlinear Dirac Neutrino Oscillations

2020 ◽  
Vol 240 ◽  
pp. 07010
Author(s):  
Zhi Hao Quek ◽  
Wei Khim Ng ◽  
Aik Hui Chan ◽  
Choo Hiap Oh
Keyword(s):  
Dirac Equation ◽  
Neutrino Oscillations ◽  
Oscillation Amplitude ◽  
Neutrino Energy ◽  
Number Density ◽  
Matter Distribution ◽  
Low Energies ◽  
Time Quantum ◽  
Matter Fields ◽  
Static Background

Neutrino oscillations are a possible way to probe beyond Standard Model physics. The propagation of Dirac neutrinos in a massive medium is governed by the Dirac equation modified with an effective Hamiltonian that de- pends on the number density of surrounding matter fields. At the same time, quantum nonlinearities may contribute to neutrino oscillations by further mod- ifying the Dirac equation. A possible nonlinearity is computationally studied using Mathematica at low energies. We find that the presence of a uniform, static background matter distribution may significantly alter the oscillation am- plitude and wavelength; the considered nonlinearity may further reduce both oscillation amplitude and wavelength. In addition, the presence of matter al- lows the effects of the nonlinearity to be more readily observed for the chosen background densities and neutrino energy.

Neutrino oscillations in a medium with variable density

1986 ◽  
Vol 150 (12) ◽  
pp. 632
Author(s):  
S.P. Mikheev ◽  
A.Yu. Smirnov
Keyword(s):  
Neutrino Oscillations ◽  
Variable Density

Shape Dynamics and the Linking Theory

2018 ◽  
Author(s):  
Flavio Mercati
Keyword(s):  
Phase Space ◽  
Degrees Of Freedom ◽  
Line Element ◽  
Hamiltonian Formulation ◽  
Operational Definition ◽  
Extended Phase Space ◽  
Extended Phase ◽  
Problem Of Time ◽  
Definition Of ◽  
Matter Fields

This chapter explains in detail the current Hamiltonian formulation of SD, and the concept of Linking Theory of which (GR) and SD are two complementary gauge-fixings. The physical degrees of freedom of SD are identified, the simple way in which it solves the problem of time and the problem of observables in quantum gravity are explained, and the solution to the problem of constructing a spacetime slab from a solution of SD (and the related definition of physical rods and clocks) is described. Furthermore, the canonical way of coupling matter to SD is introduced, together with the operational definition of four-dimensional line element as an effective background for matter fields. The chapter concludes with two ‘structural’ results obtained in the attempt of finding a construction principle for SD: the concept of ‘symmetry doubling’, related to the BRST formulation of the theory, and the idea of ‘conformogeometrodynamics regained’, that is, to derive the theory as the unique one in the extended phase space of GR that realizes the symmetry doubling idea.

scholarly journals Hierarchical structure of physical Yukawa couplings from matter field Kähler metric

2021 ◽  
Vol 2021 (7) ◽  
Author(s):  
Keiya Ishiguro ◽  
Tatsuo Kobayashi ◽  
Hajime Otsuka
Keyword(s):  
String Theory ◽  
Hierarchical Structure ◽  
Matter Field ◽  
Heterotic String ◽  
Heterotic String Theory ◽  
Kähler Metric ◽  
Yukawa Couplings ◽  
String Compactifications ◽  
Kahler Metric ◽  
Matter Fields

Abstract We study the impacts of matter field Kähler metric on physical Yukawa couplings in string compactifications. Since the Kähler metric is non-trivial in general, the kinetic mixing of matter fields opens a new avenue for realizing a hierarchical structure of physical Yukawa couplings, even when holomorphic Yukawa couplings have the trivial structure. The hierarchical Yukawa couplings are demonstrated by couplings of pure untwisted modes on toroidal orbifolds and their resolutions in the context of heterotic string theory with standard embedding. Also, we study the hierarchical couplings among untwisted and twisted modes on resolved orbifolds.

Sign in / Sign up

Export Citation Format

Share Document