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Related papers: Effective action for EPRL/FK spin foam models

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Spin foam models are an attempt for a covariant, or path integral formulation of canonical loop quantum gravity. The construction of such models usually rely on the Plebanski formulation of general relativity as a constrained BF theory and…

General Relativity and Quantum Cosmology · Physics 2015-05-13 Aristide Baratin , Cecilia Flori , Thomas Thiemann

The most common spin foam models of gravity are widely believed to be discrete path integral quantizations of the Plebanski action. However, their derivation in present formulations is incomplete and lower dimensional simplex amplitudes are…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Martin Bojowald , Alejandro Perez

We study the Heisenberg-Euler effective action in constant electromagnetic fields $\bar{F}$ for QED with $N$ charged particle flavors of the same mass and charge $e$ in the large $N$ limit characterized by sending $N\to\infty$ while keeping…

High Energy Physics - Theory · Physics 2024-02-26 Felix Karbstein

We discuss the computation of the quantum effective action of strongly interacting field theories using holographic duality, and its use to determine quasi-equilibrium parameters of first order phase transitions relevant for gravitational…

High Energy Physics - Theory · Physics 2022-03-31 Fëanor Reuben Ares , Oscar Henriksson , Mark Hindmarsh , Carlos Hoyos , Niko Jokela

This is a more detailed version of our recent paper where we proposed, from first principles, a direct method for evaluating the exact fermion propagator in the presence of a general background field at finite temperature. This can, in…

High Energy Physics - Theory · Physics 2010-03-12 Ashok Das , J. Frenkel

In this manuscript, we study the relativistic quantum mechanics of an electron in external fields in the spinning cosmic string spacetime. We obtain the Dirac equation, write the first and second-order equations from it, and then we solve…

High Energy Physics - Theory · Physics 2020-06-12 Márcio M. Cunha , Edilberto O. Silva

So far spin foam models are hardly understood beyond a few of their basic building blocks. To make progress on this question, we define analogue spin foam models, so called spin nets, for quantum groups $\text{SU}(2)_k$ and examine their…

General Relativity and Quantum Cosmology · Physics 2014-08-06 Bianca Dittrich , Mercedes Martin-Benito , Sebastian Steinhaus

We show how heavy quark effective theory, including 1/M corrections, may be matched onto dynamical quark models by making a specific choice of K,m and v in the p=mv+K expansion. We note that Wigner rotations of heavy quark spins arise at…

High Energy Physics - Phenomenology · Physics 2010-11-01 Frank Close , Zhenping Li

The effective field theory (EFT) for triaxially deformed even-even nuclei is generalized to include the vibrational degrees of freedom. The pertinent Hamiltonian is constructed up to next-to-leading order. The leading order part describes…

Nuclear Theory · Physics 2018-07-04 Q. B. Chen , N. Kaiser , Ulf-G. Meißner , J. Meng

The graphical calculus method is generalized to study the relation between covariant and canonical dynamics of loop quantum gravity. On one hand, a graphical derivation of the partition function of the generalized Euclidean…

General Relativity and Quantum Cosmology · Physics 2021-08-17 Jinsong Yang , Cong Zhang , Yongge Ma

It is known that the Einstein-Hilbert action with a positive cosmological constant can be represented as a perturbation of the SO(4,1) BF theory by a symmetry-breaking term quadratic in the B field. Introducing fermionic matter generates…

General Relativity and Quantum Cosmology · Physics 2015-06-25 A. Mikovic

We find all the spin-foams contributing in the first order of the vertex expansion to the transition amplitude of the Bianchi-Rovelli-Vidotto Dipole Cosmology model. Our algorithm is general and provides spin-foams of arbitrarily given,…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Marcin Kisielowski , Jerzy Lewandowski , Jacek Puchta

We temporally resolve the resonance fluorescence from an electron spin confined to a single self-assembled quantum dot to measure directly the spin's optical initialization and natural relaxation timescales. Our measurements demonstrate…

Mesoscale and Nanoscale Physics · Physics 2012-07-20 C. -Y. Lu , Y. Zhao , A. N. Vamivakas , C. Matthiesen , S. Fält , A. Badolato , M. Atatüre

We consider the Einstein equation with first order (semiclassical) quantum corrections. Although the quantum corrections contain up to fourth order derivatives of the metric, the solutions which are physically relevant satisfy a reduced…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Leonard Parker , Jonathan Z. Simon

It is demonstrated that, within the eikonal approach, the Coulomb corrections to the elastic electromagnetic non-flip and spin-flip proton--nucleus amplitudes are identical when the two amplitudes share the same exponential form factors.…

High Energy Physics - Phenomenology · Physics 2026-02-10 Andrei Poblaguev

We compute corrections to the Einstein field equations which are induced by the anomalous effective actions associated to the type A conformal anomaly, both for the (non-local) Riegert action, as well as for the local action with dilaton.…

High Energy Physics - Theory · Physics 2017-05-24 Hadi Godazgar , Krzysztof A. Meissner , Hermann Nicolai

We use an effective field theory (EFT) approach to calculate the next to leading order (NLO) gravitational spin-orbit interaction between two spinning compact objects. The NLO spin-orbit interaction provides the most computationally complex…

General Relativity and Quantum Cosmology · Physics 2010-12-03 Michele Levi

Following our previous work wherein the leading order effective action was computed in the covariant effective field theory of gravity, here we specialize the effective action to the FRW spacetime and obtain the effective Friedmann…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-16 Alessandro Codello , Rajeev Kumar Jain

Using the quantum effective action in the Schwinger-Keldysh formalism, we derive quantum corrections to the semiclassical Langevin dynamics of a dissipative system governed by a macroscopic degree of freedom. We discuss the connection with…

Quantum Gases · Physics 2026-05-20 Cesare Vianello , Andrea Bardin , Luca Salasnich

We consider finite volume effects on the electro-magnetic pion form factor near the chiral limit, in the so-called $\epsilon$ regime. The pseudoscalar-vector-pseudoscalar three-point function is calculated in the $\epsilon$ expansion of…

High Energy Physics - Lattice · Physics 2014-02-13 Hidenori Fukaya , Takashi Suzuki
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