Fri - 01/19/24

There is no new related paper today

Anomalies and gauging of U(1) symmetries

  • Authors: Andrea Antinucci, Francesco Benini
  • Subjects: High Energy Physics - Theory (hep-th)
  • Arxiv link: https://arxiv.org/abs/2401.10165
  • Abstract We propose the Symmetry TFT for theories with a $U(1)$ symmetry in arbitrary dimension. The Symmetry TFT describes the structure of the symmetry, its anomalies, and the possible topological manipulations. It is constructed as a BF theory of gauge fields for groups $U(1)$ and $\mathbb{R}$, and contains a continuum of topological operators. We also propose an operation that produces the Symmetry TFT for the theory obtained by dynamically gauging the $U(1)$ symmetry. We discuss many examples. As an interesting outcome, we obtain the Symmetry TFT for the non-invertible $\mathbb{Q}/\mathbb{Z}$ chiral symmetry in four dimensions.

  1. [2401.09538] - On the Holographic Dual of a Topological Symmetry Operator - Jonathan J. Heckman, Max Hübner, Chitraang Murdia

  2. [2401.09672] - Quantum Gravity Effective Action Provides Entropy of The Universe - Ken-ji Hamada

Thu - 01/18/24

Step-by-Step Canonical Quantum Gravity – Part I: Ashtekar’s New Variables

  • Authors: Lei Lu, Philip A. May
  • Subjects: General Relativity and Quantum Cosmology (gr-qc)
  • Arxiv link: https://arxiv.org/abs/2401.06863
  • Abstract Canonical quantum gravity was first developed by Abhay Ashtekar, Lee Smolin, Carlo Rovelli and their collaborators in the late 1980s. It was a major breakthrough that successfully brought Einstein’s theory of General Relativity (GR) into a Yang-Mills-type gauge theory. A new era of quantum gravity research has since started, and with decades of continued efforts from a relatively small community, the area now known as Loop Quantum Gravity (LQG) has flourished, making it a promising theory of quantum gravity. Due to its incredibly high level of complexity, many technical details were left out in introductory texts on LQG. In particular, resources that are appropriate to the undergraduate level are extremely limited. Consequently, there exists a huge gap between the knowledge base of an undergraduate physics major and the necessary readiness to carry out LQG research. In an effort to fill this gap, we aim to develop a pedagogical user guide that provides a step-by-step walk-through of canonical quantum gravity, without compromising necessary technical details. We hope that our attempt will bring more exposure to undergraduates on the exciting early developments of canonical quantum gravity, and provide them with the necessary foundation to explore active research fields such as black hole thermodynamics, Wheeler-DeWitt equation, and so on. This work will also serve as a solid base for anyone hoping to pursue further study in LQG at a higher level.

Introduction to Loop Quantum Gravity. The Holst’s action and the covariant formalism

  • Authors: L.Fatibene, A.Orizzonte, A.Albano, S.Coriasco, M.Ferraris, S.Garruto, N.Morandi
  • Subjects: General Relativity and Quantum Cosmology (gr-qc)
  • Arxiv link: https://arxiv.org/abs/2401.07307
  • Abstract We review Holst formalism and we discuss dynamical equivalence with standard GR (in dimension 4). Holst formalism is written for a spin coframe field $e^I_\mu$ and a $Spin(3,1)$-connection $\omega^{IJ}\mu$ on spacetime $M$ and it depends on the Holst parameter $\gamma\in \mathbb{R}-{0}$. We show the model is dynamically equivalent to standard GR, in the sense that up to a pointwise $Spin(3,1)$-gauge transformation acting on frame indices, solutions of the two models are in one-to-one correspondence. Hence the two models are classically equivalent. One can also introduce new variables by splitting the spin connection into a pair of a $Spin(3)$-connection $A^i\mu$ and a $Spin(3)$-valued 1-form $k^i_\mu$. The construction of these new variables relies on a particular algebraic structure, called a reductive splitting. A reductive splitting is a weaker structure than requiring that the gauge group splits as the products of two sub-groups, as it happens in Euclidean signature in the selfdual formulation originally introduced in this context by Ashtekar, and it still allows to deal with the Lorentzian signature without resorting to complexifications. The reductive splitting of $SL(2, \mathbb{C})$ is not unique and it is parameterized by a real parameter $\beta$, called the Immirzi parameter. The splitting is here done on spacetime, not on space, to obtain a $Spin(3)$-connection $A^i_\mu$, which is called the Barbero-Immirzi connection on spacetime. One obtains a covariant model depending on the fields $(e^I_\mu, A^i_\mu, k^i_\mu)$ which is again dynamically equivalent to standard GR (as well as the Holst action). Usually, in the literature one sets $\beta=\gamma$ for the sake of simplicity. Here we keep the Holst and Immirzi parameters distinct to show that eventually, only $\beta$ will survive in boundary field equations.

There is no new related paper today

  1. [2401.06902] - Primordial gravitational waves in Wheeler-DeWitt non-commutative linearized branch-cut quantum gravity - Cesar A. Zen Vasconcellos, Peter O. Hess, Fridolin Weber, Benno Bodmann, Marcelo Netz-Marzola, Dimiter Hadjimichef, Geovane Naysinger, Moises Razeira

  2. [2401.07471] - Partial entanglement network and bulk geometry reconstruction in AdS/CFT - Jiong Lin, Yizhou Lu, Qiang Wen

  3. [2401.07130] - On the interplay between boundary conditions and the Lorentzian Wetterich equation - Claudio Dappiaggi, Filippo Nava, Luca Sinibaldi

Wed - 01/17/24

There is no new related paper today

There is no new related paper today

  1. [2401.06220] - On the Random Matrix Model of the Virasoro Minimal String - Clifford V. Johnson

Tue - 01/16/24

There is no new related paper today

There is no new related paper today

  1. [2401.06220] - On the Random Matrix Model of the Virasoro Minimal String - Clifford V. Johnson

Mon - 01/15/24

There is no new related paper today

There is no new related paper today

  1. [2401.06220] - On the Random Matrix Model of the Virasoro Minimal String - Clifford V. Johnson

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