Sun - 11/06/22

There is no new related paper today

There is no new related paper today

  1. [2211.01525] - Exploring quantum geometry created by quantum matter - Abhay Ashtekar

  2. [2211.01546] - On the superstring-inspired quantum correction to the Starobinsky model of inflation - Sergei V. Ketov, Ekaterina O. Pozdeeva, Sergey Yu. Vernov

  3. [2211.01674] - Photon Rings Around Warped Black Holes - Daniel Kapec, Alexandru Lupsasca, Andrew Strominger

Sat - 11/05/22

There is no new related paper today

There is no new related paper today

  1. [2211.01525] - Exploring quantum geometry created by quantum matter - Abhay Ashtekar

  2. [2211.01546] - On the superstring-inspired quantum correction to the Starobinsky model of inflation - Sergei V. Ketov, Ekaterina O. Pozdeeva, Sergey Yu. Vernov

  3. [2211.01674] - Photon Rings Around Warped Black Holes - Daniel Kapec, Alexandru Lupsasca, Andrew Strominger

Fri - 11/04/22

There is no new related paper today

There is no new related paper today

  1. [2211.01525] - Exploring quantum geometry created by quantum matter - Abhay Ashtekar

  2. [2211.01546] - On the superstring-inspired quantum correction to the Starobinsky model of inflation - Sergei V. Ketov, Ekaterina O. Pozdeeva, Sergey Yu. Vernov

  3. [2211.01674] - Photon Rings Around Warped Black Holes - Daniel Kapec, Alexandru Lupsasca, Andrew Strominger

Thu - 11/03/22

There is no new related paper today

There is no new related paper today

  1. [2211.00743] - Regular black holes sourced by nonlinear electrodynamics - Kirill A. Bronnikov

  2. [2211.01002] - Effective de Sitter space and large-scale spectral dimension (3+1) - Carlo A. Trugenberger

Wed - 11/02/22

There is no new related paper today

  • Authors: Marc Geiller, Florian Girelli, Christophe Goeller, Panagiotis Tsimiklis
  • Subjects: High Energy Physics - Theory (hep-th); General Relativity and Quantum Cosmology (gr-qc)
  • Arxiv link: https://arxiv.org/abs/2211.00068
  • Abstract We present a Sugawara-type construction for boundary charges in 4d BF theory and in a general family of related TQFTs. Starting from the underlying current Lie algebra of boundary symmetries, this gives rise to well-defined quadratic charges forming an algebra of vector fields. In the case of 3d BF theory (i.e. 3d gravity), it was shown in [PRD 106 (2022), arXiv:2012.05263 [hep-th]] that this construction leads to a two-dimensional family of diffeomorphism charges which satisfy a certain modular duality. Here we show that adapting this construction to 4d BF theory first requires to split the underlying gauge algebra. Surprisingly, the space of well-defined quadratic generators can then be shown to be once again two-dimensional. In the case of tangential vector fields, this canonically endows 4d BF theory with a $\mathrm{diff}(S^2)\times\mathrm{diff}(S^2)$ or $\mathrm{diff}(S^2)\ltimes\mathrm{vect}(S^2)_\mathrm{ab}$ algebra of boundary symmetries depending on the gauge algebra. The prospect is to then understand how this can be reduced to a gravitational symmetry algebra by imposing Pleba'nski simplicity constraints.
  1. [2211.00517] - Truly Lorentzian quantum cosmology - Ding Jia

Tue - 11/01/22

Cosmological states in loop quantum gravity on homogeneous graphs

  • Authors: Bekir Baytas, Nelson Yokomizo
  • Subjects: General Relativity and Quantum Cosmology (gr-qc)
  • Arxiv link: https://arxiv.org/abs/2210.16439
  • Abstract We introduce a class of states characterized by proposed conditions of homogeneity and isotropy in loop quantum gravity and construct concrete examples given by Bell-network states on a special class of homogeneous graphs. Such states provide new representations of cosmological spaces that can be explored for the formulation of cosmological models in the context of loop quantum gravity. We show that their local geometry is described in an automorphism-invariant manner by one-node observables analogous to the one-body observables used in many-body quantum mechanics, and compute the density matrix representing the restriction of global states to the algebra of one-node observables. The von Neumann entropy of this density matrix provides a notion of entanglement entropy of a local region which respects automorphism-invariance and can be applied to states involving superpositions of distinct graphs.

Probing Effective Loop Quantum Gravity on Weak Gravitational Lensing, Hawking Radiation and Bounding Greybody Factor by Black Holes

  • Authors: Wajiha Javed, Mehak Atique, Ali Övgün
  • Subjects: General Relativity and Quantum Cosmology (gr-qc)
  • Arxiv link: https://arxiv.org/abs/2210.17277
  • Abstract In this paper, we study the weak deflection angle of black hole in effective loop quantum gravity using the geometrical technique used by Gibbons and Werner. We first derive the optical metric, calculate the Gaussian optical curvature, and then apply the Gauss-Bonnet theorem. We then also investigate the effect of plasma and dark matter mediums on the weak deflection angle. We show that increasing the impact of these two mediums grows the deflection angle. We also calculate the Hawking temperature via Gauss-Bonnet theorem. In addition, we determine the fermionic greybody bounds. Moreover, we discuss the graphical behaviour of the deflection angle and bounds on the greybody factor. Graphically, we observe that taking $0 < A_{\lambda} < 1$ angle ranges from negative values to maximum values and also attain maximum value for these values of $ A_{\lambda}$ and for $A_{\lambda} \geq 1$ exponentially approaches to zero. Later, we graphically investigate that the greybody factor bound exhibits the convergent behaviour by converging to $1$. We also examine that the results obtained for the black hole in effective loop quantum gravity are reduced to the Schwarzschild black hole solutions when the dimensionless non-negative parameter is equal to zero $A_{\lambda}=0$.

There is no new related paper today

  1. [2210.16856] - On Black Hole Thermodynamics, Singularity, and Gravitational Entropy - Yen Chin Ong

  2. [2210.17462] - Comment on a regular black hole with Yang-Mills hair - Piotr Bizoń, Maciej Maliborski

  3. [2210.16459] - Non-Gaussianities in generalized non-local $R^2$-like inflation - Alexey S. Koshelev, K. Sravan Kumar, Alexei A. Starobinsky

Mon - 10/31/22

There is no new related paper today

There is no new related paper today

  1. [2210.15980] - A Phase of Gravity without Hamiltonian Constraint - Sandipan Sengupta

  2. [2210.15682] - Meson content of entanglement spectra after integrable and nonintegrable quantum quenches - Johannes Knaute

  3. [2210.16072] - Form Factors in Asymptotically Safe Quantum Gravity - Benjamin Knorr, Chris Ripken, Frank Saueressig

  4. [2210.16159] - Power-Yang-Mills black holes and black branes in quartic quasi-topological gravity - Askar Ali, Khalid Saifullah

New papers last week