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Related papers: How `Complex' is the Dirac Equation?

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We develop an Hamiltonian representation of the sl(2,C) algebra on a phase space consisting of N copies of twistors, or bi-spinors. We identify a complete set of global invariants, and show that they generate a closed algebra including…

General Relativity and Quantum Cosmology · Physics 2015-05-28 Maité Dupuis , Laurent Freidel , Etera R. Livine , Simone Speziale

The Dirac equation is one of the most fundamental equations of modern physics. It is a spinor equation, but some tensor equivalents of the equation were proposed previously. Those equivalents were either nonlinear or involved several…

Quantum Physics · Physics 2024-08-21 Andrey Akhmeteli

We study $(2+1)$ dimensional Dirac equation with complex scalar and Lorentz scalar potentials. It is shown that the Dirac equation admits exact analytical solutions with real eigenvalues for certain complex potentials while for another…

Quantum Physics · Physics 2015-06-22 C. -L. Ho , P. Roy

In a recent paper [1] we have constructed the spin and tensor representations of SO(4) from which the invariant weight can be derived for the Barrett-Crane model in quantum gravity. By analogy with the SO(4) group, we present the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 M. Lorente

Tensor and matrix formulations of Dirac-K\"ahler equation for massive and massless fields are considered. The equation matrices obtained are simple linear combinations of matrix elements in the 16-dimensional space. The projection…

High Energy Physics - Theory · Physics 2011-07-19 S. I. Kruglov

We start from a noncompact Lie algebra isomorphic to the Dirac algebra and relate this Lie algebra in a brief review to low energy hadron physics described by the compact group SU(4). This step permits an overall physical identification of…

General Physics · Physics 2013-06-13 Rolf Dahm

Parametrization of complex 4 x 4 - matrices G in terms of Dirac tensor parameters (A,B,A_{l},B_{l},F_{kl}) or equivalent four complex 4-vectors (k,m,n,l) is investigated. In the given parametrization, the problem of inverting any 4 x 4…

High Energy Physics - Theory · Physics 2008-02-15 V. M. Red'kov , A. A. Bogush , N. G. Tokarevskaya

It is shown that the hypercomplex Dirac equation describes the system of connected fields: 4-scalar, 4-pseudoscalar, 4-vector, 4-pseudo-vector and antisymmetric 4-tensor second rank field. If mass is assumed to be zero this system splits…

Quantum Physics · Physics 2007-05-23 K. S. Karplyuk , O. O. Zhmudskyy

We derive the stabiliser group of the four-vector, also known as Wigner's little group, in case of massless particle states, as the maximal solvable subgroup of the proper orthochronous Lorentz group of dimension four, known as the Borel…

General Physics · Physics 2024-01-12 Stefan Groote , Rein Saar

In this note we prove a representation theorem for the symmetric cone automorphisms in the spin algebra\, $\Ln$.

Optimization and Control · Mathematics 2021-03-19 Roman Sznajder

The presentation makes use of geometric algebra, also known as Clifford algebra, in 5-dimensional spacetime. The choice of this space is given the character of first principle, justified solely by the consequences that can be derived from…

Quantum Physics · Physics 2009-11-13 Jose B. Almeida

Parametrization of $4\times 4$-matrices $G$ of the complex linear group $GL(4,C)$ in terms of four complex 4-vector parameters $(k,m,n,l)$ is investigated. Additional restrictions separating some subgroups of $GL(4,C)$ are given explicitly.…

Mathematical Physics · Physics 2008-04-25 Victor M. Red'kov , Andrei A. Bogush , Natalia G. Tokarevskaya

Recently Alberto Elduque listed all simple and graded modulo 2 finite dimensional Lie algebras and superalgebras whose odd component is the spinor representation of the orthogonal Lie algebra equal to the even component, and discovered one…

Representation Theory · Mathematics 2007-05-23 Sofiane Bouarroudj , Pavel Grozman , Dimitry Leites

The formulation of quantum mechanics with a complex Hilbert space is equivalent to a formulation with a real Hilbert space and particular density matrix and observables. We study the real representations of the Poincare group, motivated by…

Mathematical Physics · Physics 2014-07-25 Leonardo Pedro

The triality properties of Dirac spinors are studied, including a construction of the algebra of (complexified) biquaternion. It is proved that there exists a vector-representation of Dirac spinors. The massive Dirac equation in the…

Mathematical Physics · Physics 2007-05-23 Liu Yu-Fen

Supergroups are defined in the framework of $\dZ_2$-graded Clifford algebras over the fields of real and complex numbers, respectively. It is shown that cyclic structures of complex and real supergroups are defined by Brauer-Wall groups…

Mathematical Physics · Physics 2014-10-03 V. V. Varlamov

Hypercubic groups in any dimension are defined and their conjugate classifications and representation theories are derived. Double group and spinor representation are introduced. A detailed calculation is carried out on the structures of…

High Energy Physics - Lattice · Physics 2015-06-25 Jian Dai , Xing-Chang Song

The second-order modified Dirac equation leading to the modified dispersion relation due to the Lorentz invariance violation corrections is suggested. The equation is formulated in the 16-component first- order form. I have obtained the…

General Relativity and Quantum Cosmology · Physics 2013-01-03 S. I. Kruglov

In part I of [1] we have developed the tensor and spin representation of SO(4) in order to apply it to the simplicial decomposition of the Barrett-Crane model. We attach to each face of a triangle the spherical function constructed from the…

General Relativity and Quantum Cosmology · Physics 2008-04-30 P. Kramer , M. Lorente

The extension of nonlinear higher-spin equations in d=4 proposed in [arXiv:1504.07289] for the construction of invariant functional is shown to respect local Lorentz symmetry. The equations are rewritten in a manifestly Lorentz covariant…

High Energy Physics - Theory · Physics 2018-07-31 V. E. Didenko , N. G. Misuna , M. A. Vasiliev