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Related papers: LQG propagator: III. The new vertex

200 papers

The electromagnetic interaction with quarks is investigated through a relativistic, electromagnetic gauge-invariant treatment. Gluon dressing of the quark-photon vertex and the quark self-energy functions is described by the inhomogeneous…

Nuclear Theory · Physics 2009-09-25 Michael R. Frank

In this work, it is demonstrated how the kinematical Hilbert space of Loop Quantum Gravity (LQG) can be inferred from the configuration space of BF theories via the imposition of the Hamiltonian constraints. In particular, it is outlined…

General Relativity and Quantum Cosmology · Physics 2015-05-20 Francesco Cianfrani

We describe a new approach to gravitational instability in large-scale structure, where the equations of motion are written and solved as in field theory in terms of Feynman diagrams. The basic objects of interest are the propagator (which…

Astrophysics · Physics 2015-06-24 Roman Scoccimarro

This is the third of a series of papers treating light baryon resonances up to 3 GeV within a relativistically covariant quark model based on the Bethe-Salpeter equation with instantaneous two- and three-body forces. In this last paper we…

High Energy Physics - Phenomenology · Physics 2009-11-07 Ulrich Loering , Bernard Ch. Metsch , Herbert R. Petry

We study the problem of semiclassical limit of Loop Quantum Gravity theory defined by the new spin foam models. This is done by analyzing the large-spin asymptotics of the Hartle-Hawking wavefunction. By using the stationary phase method we…

General Relativity and Quantum Cosmology · Physics 2011-08-01 Aleksandar Mikovic , Marko Vojinovic

We treat general relativity as an effective field theory, obtaining the full nonanalytic component of the scattering matrix potential to one-loop order. The lowest order vertex rules for the resulting effective field theory are presented…

High Energy Physics - Theory · Physics 2014-11-18 N. E. J Bjerrum-Bohr , John F. Donoghue , Barry R. Holstein

In the two previous papers of this series we defined a new combinatorical approach to quantum gravity, Algebraic Quantum Gravity (AQG). We showed that AQG reproduces the correct infinitesimal dynamics in the semiclassical limit, provided…

General Relativity and Quantum Cosmology · Physics 2008-11-26 K. Giesel , T. Thiemann

As established in a prior work of the author, the linear simplicity constraints used in the construction of the so-called `new' spin-foam models mix three of the five sectors of Plebanski theory as well as two dynamical orientations, and…

General Relativity and Quantum Cosmology · Physics 2013-09-16 Jonathan Engle

Within the Asymptotic Safety scenario, we discuss whether Quantum Einstein Gravity (QEG) can give rise to a semi-classical regime of propagating physical gravitons (gravitational waves) governed by an effective theory which complies with…

High Energy Physics - Theory · Physics 2015-06-22 Daniel Becker , Martin Reuter

The efforts in this contribution consist in reassessing a modified Dirac equation that incorporates a $\gamma^0 \gamma_5$-Lorentz-symmetry violating (LSV) term induced as a Loop Quantum Gravity (LQG) effect. Originally, this equation has…

High Energy Physics - Theory · Physics 2024-09-19 João Paulo S. Melo , Mario J. Neves , Jefferson M. A. Paixão , José A. Helayël-Neto

We reconstruct the Lorentzian graviton propagator in asymptotically safe quantum gravity from Euclidean data. The reconstruction is applied to both the dynamical fluctuation graviton and the background graviton propagator. We prove that the…

High Energy Physics - Theory · Physics 2022-01-05 Alfio Bonanno , Tobias Denz , Jan M. Pawlowski , Manuel Reichert

A calculation of the one loop gravitational self-energy graph in non-anticommutative quantum gravity reveals that graviton loops are damped by internal momentum dependent factors in the modified propagator and the vertex functions. The…

High Energy Physics - Theory · Physics 2016-03-29 J. W. Moffat

Asymptotically Safe theories of gravity have recently received much attention. In this work we discuss a class of inflationary models derived from quantum-gravity modification of quadratic gravity according to the induced scaling around the…

General Relativity and Quantum Cosmology · Physics 2015-10-14 Alfio Bonanno , Alessia Platania

We demonstrate that QCD gluon amplitudes can be used to construct a Lagrangian for gravity. This procedure makes use of perturbative `squaring' relations between gravity and gauge theory that follow from string theory. We explicitly carry…

High Energy Physics - Theory · Physics 2009-10-31 Z. Bern , A. K. Grant

We discuss how to consistently perform effective Lagrangian computations in quantum gravity with branes in compact extra dimensions. A reparametrization invariant and infrared finite result is obtained in a non trivial way. It is crucial to…

High Energy Physics - Phenomenology · Physics 2014-03-17 R. Contino , L. Pilo , R. Rattazzi , A. Strumia

In this paper we have calculated the spectral dimension of loop quantum gravity (LQG) using simple arguments coming from the area spectrum at different length scales. We have obtained that the spectral dimension of the spatial section runs…

General Relativity and Quantum Cosmology · Physics 2010-01-30 Leonardo Modesto

We compute the graviton-mediated two-to-two scattering amplitude and cross section for scalar particles in asymptotically safe quantum gravity. Specifically, we compute the full momentum dependence of the scalar-graviton three-point…

High Energy Physics - Theory · Physics 2026-03-12 Angelo P. Chiesa , Jan M. Pawlowski , Manuel Reichert

We quantise the new connection formulation of D+1 dimensional General Relativity developed in our companion papers by Loop Quantum Gravity (LQG) methods. It turns out that all the tools prepared for LQG straightforwardly generalise to the…

General Relativity and Quantum Cosmology · Physics 2013-02-13 Norbert Bodendorfer , Thomas Thiemann , Andreas Thurn

Making use of the Stochastic Vacuum Model and the gluon gauge-invariant two-point correlation function, determined by numerical simulation on the lattice in both quenched approximation and full QCD, we calculate the elementary (quark-quark)…

High Energy Physics - Phenomenology · Physics 2009-11-10 A. F. Martini , M. J. Menon

We study the graviton propagator in euclidean loop quantum gravity, using the spinfoam formalism. We use boundary-amplitude and group-field-theory techniques, and compute one component of the propagator to first order, under a number of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Carlo Rovelli