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Related papers: Immirzi parameter in the Barrett-Crane model?

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We introduce a dual formulation of group field theories, making them a type of non-commutative field theories. In this formulation, the variables of the field are Lie algebra variables with a clear interpretation in terms of simplicial…

High Energy Physics - Theory · Physics 2010-12-03 Aristide Baratin , Daniele Oriti

We discuss various features and details of two versions of the Barrett-Crane spin foam model of quantum gravity, first of the Spin(4)-symmetric Riemannian model and second of the SL(2,C)-symmetric Lorentzian version in which all tetrahedra…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Hendryk Pfeiffer

We study Fermi liquids with a Fermi surface that lacks continuous rotational invariance, and in the presence of an arbitrary quartic interaction. We obtain the expressions of the generalized static susceptibilities that measure the linear…

Strongly Correlated Electrons · Physics 2017-07-24 Pablo Rodríguez-Ponte , Nicolás Grandi , Daniel C. Cabra

A long-wavelength, low-frequency effective theory is obtained from $t_1-t_2-J$ model. The action is written in terms of two-component bose spinor fields (CP^1 fields) and two spinless Fermi fields. The generalized CP^1 model is invariant…

Condensed Matter · Physics 2016-08-31 Naoum Karchev

BF theory is a topological theory that can be seen as a natural generalization of 3-dimensional gravity to arbitrary dimensions. Here we show that the coupling to point particles that is natural in three dimensions generalizes in a direct…

General Relativity and Quantum Cosmology · Physics 2008-11-26 John C. Baez , Alejandro Perez

It is shown that the commonly accepted definition for the Casimir scalar operators of the Poincare group does not satisfy the properties of Casimir invariance when applied to the non-inertial motion of elementary particles while in the…

High Energy Physics - Theory · Physics 2010-11-24 Dinesh Singh , Nader Mobed

The purpose of this Comment is to point out that the results presented in the appendix of M. Mondragon and M. Montesinos, J. Math. Phys. 47, 022301 (2006) provides a generic method so as to deal with cases as those of Section 6 of R.…

General Relativity and Quantum Cosmology · Physics 2015-06-11 Mauricio Mondragon

The use of internal variables for the description of relativistic particles with arbitrary mass and spin in terms of scalar functions is reviewed and applied to the stochastic phase space formulation of quantum mechanics. Following Bacry…

General Relativity and Quantum Cosmology · Physics 2011-07-19 W. Drechsler

The amplitude for a spin foam in the Barrett-Crane model of Riemannian quantum gravity is given as a product over its vertices, edges and faces, with one factor of the Riemannian 10j symbols appearing for each vertex, and simpler factors…

General Relativity and Quantum Cosmology · Physics 2009-11-07 John C. Baez , J. Daniel Christensen

The paper is devoted to the study of BRST charge in perturbed two dimensional conformal field theory. The main goal is to write the operator equation expressing the conservation law of BRST charge in perturbed theory in terms of purely…

High Energy Physics - Theory · Physics 2008-11-26 Anton M. Zeitlin

This work is a continuation of studies presented in the papers arXiv:0911.5597, arXiv:1003.4523. In the work it is demonstrated that with the use of one and the same parameter deformation may be described for several cases of the General…

General Relativity and Quantum Cosmology · Physics 2010-06-28 A. E. Shalyt-Margolin

In this paper we research all possible finite-dimensional representations and corresponding values of the Barbero-Immirzi parameter contained in EPRL simplicity constraints by using Naimark's fundamental theorem of the Lorentz group…

General Relativity and Quantum Cosmology · Physics 2017-09-12 Leonid Perlov , Michael Bukatin

Recent results in Local Regge Calculus are confronted with Spin Foam Formalism. Introducing Barrett-Crane Quantization in Local Regge Calculus makes it possible to associate a unique Spin $j_{h}$ with an hinge $h$, fulfilling one of the…

General Relativity and Quantum Cosmology · Physics 2012-01-25 Gabriele Gionti , S. J

Generalized spin-boson (GSB) models describe the interaction between a quantum mechanical system and a structured boson environment, mediated by a family of coupling functions known as form factors. We propose an extension of the class of…

Mathematical Physics · Physics 2022-07-15 Davide Lonigro

We study a family of (possibly non topological) deformations of $BF$ theory for the Lie algebra obtained by quadratic extension of $\mathfrak{so}(3,1)$ by an orthogonal module. The resulting theory, called quadratically extended General…

Mathematical Physics · Physics 2024-07-02 Alberto S. Cattaneo , Leon Menger , Michele Schiavina

In spin-lattice models with order parameter conserved, we generalize the idea of spin diffusion incorporating a variety factors as possible driving forces, including the external field and the temperature. The Kawasaki dynamics in the…

Statistical Mechanics · Physics 2007-05-23 Han Zhu , Jian-Yang Zhu

We study the state-sum models of quantum gravity based on a representation 2-category of the Poincare 2-group. We call them spin-cube models, since they are categorical generalizations of spin-foam models. A spin-cube state sum can be…

General Relativity and Quantum Cosmology · Physics 2015-06-15 A. Mikovic

Spatial stochastic processes that are modeled over the entire Earth's surface require statistical approaches that directly consider the spherical domain. Here, we extend the notion of intrinsic random functions (IRF) to model non-stationary…

Statistics Theory · Mathematics 2016-06-08 Chunfeng Huang , Haimeng Zhang , Scott M. Robeson , Jacob Shields

In order to introduce an interaction between gravity and fermions in the Ashtekar-Barbero-Immirzi formalism without affecting classical dynamics a non-minimal term is necessary. The non-minimal term together with the Holst modification to…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Simone Mercuri

It has been shown in [1] that a class of restricted spin foam models can feature a reduced spectral dimension of space-time. However, it is still an open question how curvature affects the flow of the spectral dimension. To answer this…

General Relativity and Quantum Cosmology · Physics 2023-09-18 Alexander Jercher , Sebastian Steinhaus , Johannes Thürigen