scholarly journals Field Theory of Particles with Arbitrary Spin

1977 ◽  
Vol 30 (1) ◽  
pp. 1 ◽  
Author(s):  
HS Green
Keyword(s):  
Field Theory ◽  
Dynamical Symmetry ◽  
Arbitrary Spin ◽  
De Sitter ◽  
Interacting Particles ◽  
Field Equations ◽  
Sitter Group ◽  
Finite Dimensional ◽  
General Field ◽  
Higher Spin

It is pointed out that existing field equations for particles of higher spin are unsuitable' for the formulation of field theories with interaction. ' A generalization of the Dirac and Kemmer matrices is discussed in terms of finite-dimensional representations of the de, Sitter group. ' It is shown how to formulate a general field theory in such a way as to exhibit a corresponding dynamical symmetry. The resulting field equation resembles Bhabha's, but is self-consistent in its applications to interacting particles and has a different type of mass spectrum. In the Appendix, it is shown that'within any'irreducible representation of the Poincare group there are finite-dimensional representations of the'Lorentz group'labelled (s, � s).

scholarly journals Towards causal patch physics in dS/CFT

2018 ◽  
Vol 168 ◽  
pp. 01007 ◽  
Author(s):  
Yasha Neiman
Keyword(s):  
Field Theory ◽  
Higher Spin Gravity ◽  
De Sitter Space ◽  
Vector Model ◽  
Status Report ◽  
Quantum Field ◽  
Cosmological Horizon ◽  
De Sitter ◽  
Higher Spin ◽  
Holographic Description

This contribution is a status report on a research program aimed at obtaining quantum-gravitational physics inside a cosmological horizon through dS/CFT, i.e. through a holographic description at past/future infinity of de Sitter space. The program aims to bring together two main elements. The first is the observation by Anninos, Hartman and Strominger that Vasiliev’s higher-spin gravity provides a working model for dS/CFT in 3+1 dimensions. The second is the proposal by Parikh, Savonije and Verlinde that dS/CFT may prove more tractable if one works in so-called “elliptic” de Sitter space – a folded-in-half version of global de Sitter where antipodal points have been identified. We review some relevant progress concerning quantum field theory on elliptic de Sitter space, higher-spin gravity and its holographic duality with a free vector model. We present our reasons for optimism that the approach outlined here will lead to a full holographic description of quantum (higher-spin) gravity in the causal patch of a de Sitter observer.

scholarly journals Dimensionally Compactified Chern-Simon Theory in 5D as a Gravitation Theory in 4D

2017 ◽  
Vol 45 ◽  
pp. 1760005 ◽  
Author(s):  
Ivan Morales ◽  
Bruno Neves ◽  
Zui Oporto ◽  
Olivier Piguet
Keyword(s):  
Dimensional Space ◽  
Cosmological Solution ◽  
Space Time ◽  
Gravitation Theory ◽  
Simons Theory ◽  
De Sitter ◽  
Field Equations ◽  
Sitter Group ◽  
Dimensional Space Time ◽  
Chern Simons

We propose a gravitation theory in 4 dimensional space-time obtained by compacting to 4 dimensions the five dimensional topological Chern-Simons theory with the gauge group SO(1,5) or SO(2,4) – the de Sitter or anti-de Sitter group of 5-dimensional space-time. In the resulting theory, torsion, which is solution of the field equations as in any gravitation theory in the first order formalism, is not necessarily zero. However, a cosmological solution with zero torsion exists, which reproduces the Lambda-CDM cosmological solution of General Relativity. A realistic solution with spherical symmetry is also obtained.

A GEOMETRIC FIELD THEORY OF CLOSED STRINGS: D=4, N=1 LOOP SUPERGRAVITY

1990 ◽  
Vol 05 (09) ◽  
pp. 1819-1832
Author(s):  
Leonardo Castellani
Keyword(s):  
Field Theory ◽  
Classical Field Theory ◽  
Energy Limit ◽  
Field Equations ◽  
Mass Generation ◽  
Infinite Dimensional ◽  
Internal Loop ◽  
Higher Spin ◽  
Spin Fields ◽  
Kaluza Klein

We present a classical field theory of interacting loops, whose low energy limit is D=4, N=1 supergravity. In Fourier modes, the theory is obtained by gauging the infinite dimensional algebra KM (SuperPoincaré) ⊕ Virasoro, where KM indicates the Kac-Moody extension. Taylor expanding the superloop vielbein in the “internal” coordinates yields towers of D=4 fields with arbitrarily high spins. The superloop diffeomorphisms relate all the higher spin fields. The field equations are obtained by requiring the closure of the generalized supersymmetries. Two different mechanisms give rise to masses for the higher modes: (i) a Kaluza-Klein type mass generation from “internal” loop coordinates, (ii) a non-vanishing background value for the zero mode of the Virasoro gauge field.

Polarization tensor in de Sitter gauge gravity

2021 ◽  
pp. 2150035
Author(s):  
R. Raziani ◽  
M. V. Takook
Keyword(s):  
Tensor Field ◽  
Vector Fields ◽  
Polarization Tensor ◽  
De Sitter ◽  
Field Equations ◽  
Tensor Fields ◽  
Sitter Group ◽  
Generalized Polarization ◽  
Mixed Symmetry ◽  
Symmetry Rank

The gauge theory of the de Sitter group, [Formula: see text], in the ambient space formalism has been considered in this paper. This method is important to construction of the de Sitter super-conformal gravity and Quantum gravity. [Formula: see text] gauge vector fields are needed which correspond to [Formula: see text] generators of the de Sitter group. Using the gauge-invariant Lagrangian, the field equations of these vector fields have been obtained. The gauge vector field solutions are recalled. By using these solutions, the spin-[Formula: see text] gauge potentials has been constructed. There are two possibilities for presenting this tensor field: rank-[Formula: see text] symmetric and mixed symmetry rank-[Formula: see text] tensor fields. To preserve the conformal transformation, a spin-[Formula: see text] field must be represented by a mixed symmetry rank-[Formula: see text] tensor field, [Formula: see text]. This tensor field has been rewritten in terms of a generalized polarization tensor field and a de Sitter plane wave. This generalized polarization tensor field has been calculated as a combination of vector polarization, [Formula: see text], and tensor polarization of rank-2, [Formula: see text], which can be used in the gravitational wave consideration. There is a certain extent of arbitrariness in the choice of this tensor and we fix it in such a way that, in the limit, [Formula: see text], one obtains the polarization tensor in Minkowski spacetime. It has been shown that under some simple conditions, the spin-[Formula: see text] mixed symmetry rank-[Formula: see text] tensor field can be simultaneously transformed by unitary irreducible representation of de Sitter and conformal groups ([Formula: see text]).

scholarly journals Some Properties of Massless Particles in Arbitrary Dimensions

1998 ◽  
Vol 10 (08) ◽  
pp. 1079-1109 ◽  
Author(s):  
Mourad Laoues
Keyword(s):  
Tensor Product ◽  
Arbitrary Spin ◽  
Space Time ◽  
De Sitter ◽  
Sitter Group ◽  
Massless Particles ◽  
Arbitrary Dimensions ◽  
The One

Various properties of two kinds of massless representations of the n-conformal (or (n+1)-De Sitter) group [Formula: see text] are investigated for n≥2. It is found that, for space-time dimensions n≥3, the situation is quite similar to the one of the n=4 case for Sn-massless representations of the n-De Sitter group [Formula: see text]. These representations are the restrictions of the singletons of [Formula: see text]. The main difference is that they are not contained in the tensor product of two UIRs with the same sign of energy when n>4, whereas it is the case for another kind of massless representations. Finally some examples of Gupta–Bleuler triplets are given for arbitrary spin and n≥3.

scholarly journals Quantum Electrodynamics of Particles with Arbitrary Spin

1978 ◽  
Vol 31 (4) ◽  
pp. 219
Author(s):  
HS Green
Keyword(s):  
Quantum Electrodynamics ◽  
Particle Density ◽  
Electromagnetic Coupling ◽  
Arbitrary Spin ◽  
Positive Definite ◽  
Careful Attention ◽  
Field Equations ◽  
Gauge Invariant ◽  
Electromagnetic Interactions ◽  
Higher Spin

A generalization of quantum electrodynamics is developed for particles of higher spin, with careful attention to the requirements of consistency, causality, unitarity and renormalizability. It is shown that field equations studied previously by the author are expressible in arbitrarily many different forms, which are equivalent in the absence of electromagnetic interactions, but not when electromagnetic coupling is introduced in a gauge-invariant way. A form is chosen which satisfies the requirements of causality. It is shown how to define a particle density, which is positive-definite in the subspace spanned by solutions of the field equation, and satisfies a Lorentz-invariant conservation law. The quantization and renormalization of the resulting electrodynamics is studied, and is found to require only minor modifications of the existing theory for particles of spin t.

scholarly journals On the Group-Theoretical Approach to Relativistic Wave Equations for Arbitrary Spin

2021 ◽  
Author(s):  
Luca Nanni
Keyword(s):  
Mass Spectrum ◽  
Wave Equations ◽  
Relativistic Equation ◽  
Physical Nature ◽  
Physical Reality ◽  
Arbitrary Spin ◽  
Theoretical Physics ◽  
De Sitter ◽  
Sitter Group ◽  
Algebraic Approaches

Formulating a relativistic equation for particles with arbitrary spin remains an open challenge in theoretical physics. In this study, the main algebraic approaches used to generalize the Dirac and Kemmer–Duffin equations for particles of arbitrary spin are investigated. It is proved that an irreducible relativistic equation formulated using spin matrices satisfying the commutation relations of the de Sitter group leads to inconsistent results, mainly as a consequence of violation of unitarity and the appearance of a mass spectrum that does not reflect the physical reality of elementary particles. However, the introduction of subsidiary conditions resolves the problem of unitarity and restores the physical meaning of the mass spectrum. The equations obtained by these approaches are solved and the physical nature of the solutions is discussed.

scholarly journals Particle creation in global de Sitter space: Bulk space consideration

2015 ◽  
Vol 24 (07) ◽  
pp. 1550052 ◽  
Author(s):  
M. Reza Tanhayi
Keyword(s):  
Plane Wave ◽  
Massive Particle ◽  
Particle Creation ◽  
Flat Space ◽  
De Sitter Space ◽  
Point Of View ◽  
Theoretical Point ◽  
De Sitter ◽  
Field Equations ◽  
Higher Spin

Recently in [P. R. Anderson and E. Mottola, Phys. Rev. D 89 (2014) 104039, arXiv:1310.1963 [gr-qc] and P. R. Anderson and E. Mottola, Phys. Rev. D 89 (2014) 104038, arXiv:1310.0030 [gr-qc].], it was shown that global de Sitter space is unstable even to the massive particle creation with no self-interactions. In this paper, we study the instability by making use of the coordinate-independent plane wave in de Sitter space. Within this formalism, we show that the previous results of instability of de Sitter space due to the particle creation can be generalized to higher-spin fields in a straightforward way. The so-called plane wave is defined globally in de Sitter space and de Sitter invariance is manifest since such modes are deduced from the group theoretical point of view by means of the Casimir operators. In fact, we employ the symmetry of embedding space namely the 4 + 1-dimensional flat space to write the field equations and the solutions can be obtained in terms of the plane wave in embedding space.

Sign in / Sign up

Export Citation Format

Share Document