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Related papers: Fermion Doubling in Loop Quantum Gravity

200 papers

We propose a new type of gauge in two-dimensional quantum gravity. We investigate pure gravity in this gauge, and find that the system reduces to quantum mechanics of loop length $l$. Furthermore, we rederive the $c\!=\!0$ string field…

High Energy Physics - Theory · Physics 2009-10-22 M. Fukuma , N. Ishibashi , H. Kawai , M. Ninomiya

This introductory review is addressed to beginning researchers. Some of the distinguishing features of loop quantum gravity are illustrated through loop quantum cosmology of FRW models. In particular, these examples illustrate: i) how…

General Relativity and Quantum Cosmology · Physics 2010-11-11 Abhay Ashtekar

A link between canonical quantum gravity and fermionic quantum field theory is established in this paper. From a spectral triple construction which encodes the kinematics of quantum gravity semi-classical states are constructed which, in a…

High Energy Physics - Theory · Physics 2011-05-03 Johannes Aastrup , Jesper M. Grimstrup

Minimally doubled fermions have been proposed as a cost-effective realization of chiral symmetry at non-zero lattice spacing. Using lattice perturbation theory at one loop, we study their renormalization properties. Specifically, we…

High Energy Physics - Lattice · Physics 2015-05-13 Stefano Capitani , Johannes Weber , Hartmut Wittig

This work pioneers the quantization of primordial fermion perturbations in hybrid Loop Quantum Cosmology (LQC). We consider a Dirac field coupled to a spatially flat, homogeneous, and isotropic cosmology, sourced by a scalar inflaton, and…

General Relativity and Quantum Cosmology · Physics 2017-09-08 Beatriz Elizaga Navascués , Mercedes Martín-Benito , Guillermo A. Mena Marugán

Representing massless Dirac fermions on a spatial lattice poses a potential challenge known as the Fermion Doubling problem. Addition of a quadratic term to the Dirac Hamiltonian circumvents this problem. We show that the modified…

Mesoscale and Nanoscale Physics · Physics 2015-09-15 K. M. Masum Habib , Redwan N. Sajjad , Avik W. Ghosh

We formulate Hamiltonian vector-like lattice gauge theory using the overlap formula for the spatial fermionic part, $H_f$. We define a chiral charge, $Q_5$ which commutes with $H_f$, but not with the electric field term. There is an…

High Energy Physics - Lattice · Physics 2007-05-23 Michael Creutz , Ivan Horváth , Herbert Neuberger

Based on the Pauli principle and Heisenberg uncertainty relationship, we show that the phenomenon of vectorlike fermion-doubling in quantum field theories on a lattice is related to the phenomenon of pair-creation of massless fermions, due…

High Energy Physics - Lattice · Physics 2007-05-23 She-Sheng Xue

We propose a regularized lattice model for quantum gravity purely formulated in terms of fermions. The lattice action exhibits local Lorentz symmetry, and the continuum limit is invariant under general coordinate transformations. The metric…

High Energy Physics - Theory · Physics 2015-05-30 C. Wetterich

The construction of effective Hamiltonians describing corrections to flat space particle dynamics arising from the granularity of space at very short distances is discussed in the framework of an heuristic approach to the semiclassical…

High Energy Physics - Phenomenology · Physics 2008-11-26 Luis F. Urrutia

We study the impact of quantum gravity on a system of chiral fermions that are charged under an Abelian gauge group. Under the impact of quantum gravity, a finite value of the gauge coupling could be generated and in turn drive four-fermion…

High Energy Physics - Theory · Physics 2021-06-02 Gustavo P. de Brito , Astrid Eichhorn , Marc Schiffer

We present a detailed Hamiltonian treatment of an inhomogeneous fermionic perturbation propagating on a closed FLRW spacetime quantized via LQC. Expanding the fermion in spinor harmonics on spatial 3-sphere and truncating at quadratic…

General Relativity and Quantum Cosmology · Physics 2025-10-02 Yaser Tavakoli , Ahad K. Ardabili , Sara Mosaddegh

One of the major issues confronting theoretical physics is finding a quantum theory of gravity and a resolution to the cosmological constant problem. It is believed that a true quantum theory of gravity will lead to a solution to the this…

High Energy Physics - Theory · Physics 2007-09-05 Edward Tetteh-Lartey

Simulations of supersymmetric field theories on the lattice with (spontaneously) broken supersymmetry suffer from a fermion sign problem related to the vanishing of the Witten index. We propose a novel approach which solves this problem in…

High Energy Physics - Lattice · Physics 2015-09-07 David Baumgartner , Urs Wenger

A simple model is constructed which allows to compute modified dispersion relations with effects from loop quantum gravity. Different quantization choices can be realized and their effects on the order of corrections studied explicitly. A…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Martin Bojowald , Hugo A. Morales-Tecotl , Hanno Sahlmann

The helicity flip of a spin-${\textstyle \frac{1}{2}}$ Dirac particle interacting gravitationally with a scalar field is analyzed in the context of linearized quantum gravity. It is shown that massive fermions may have their helicity…

General Relativity and Quantum Cosmology · Physics 2009-10-22 R. Aldrovandi , G. E. A. Matsas , S. F. Novaes , D. Spehler

The quantization of the Hamiltonian for a scalar field is performed in the framework of Quantum Reduced Loop Gravity. We outline how the regularization can be performed by using the analogous tools adopted in full Loop Quantum Gravity and…

General Relativity and Quantum Cosmology · Physics 2015-12-23 Jakub Bilski , Emanuele Alesci , Francesco Cianfrani

We numerically analyze the feasibility of a platform-neutral, general strategy to perform quantum simulations of fermionic lattice field theories under open boundary conditions. The digital quantum simulator requires solely one- and…

In this letter we show that the overlap formulation of chiral gauge theories correctly reproduces the gravitational Lorentz anomaly in 2-dimensions. This formulation has been recently suggested as a solution to the fermion doubling problem…

High Energy Physics - Theory · Physics 2009-12-30 S. Randjbar-Daemi , J. Strathdee

The Hamiltonian formulation of scalar-tensor theories of gravity is derived from their Lagrangian formulation by Hamiltonian analysis. The Hamiltonian formalism marks off two sectors of the theories by the coupling parameter $\omega(\phi)$.…

General Relativity and Quantum Cosmology · Physics 2015-05-28 Xiangdong Zhang , Yongge Ma