Fri - 12/20/24

**Title:

      Revisiting the Immirzi parameter: Landauer's principle and alternative entropy frameworks in Loop Quantum Gravity**  - **Authors:** Jorge Ananias Neto, Ronaldo Thibes  - **Subjects:** Subjects: General Relativity and Quantum Cosmology (gr-qc)  - **Arxiv link:** [https://arxiv.org/abs/](https://arxiv.org/abs/)  - **Abstract**  This paper investigates the implications from area quantization in Loop Quantum Gravity, particularly focusing on the application of the Landauer principle -- a fundamental thermodynamic concept establishing a connection between information theory and thermodynamics. By leveraging the Landauer principle in conjunction with the Bekenstein-Hawking entropy law, we derive the usual value for the Immirzi parameter precisely, $\gamma = \ln2/(\pi \sqrt{3})$, without using the typical procedure that involves the Boltzmann-Gibbs entropy. Furthermore, following an analogous procedure, we derive a modified expression for the Immirzi parameter aligned with Barrow's entropy formulation. Our analysis also yields a new expression for the Immirzi parameter consistent with a corresponding modified Kaniadakis entropy for black hole entropy further illustrating, along with Barrow's entropy, the applicability of Landauer's principle in alternative statistical contexts within black hole physics.

There is no new related paper today

  1. [] - Title: Euclidean teleparallel relativity and black hole partition functions - Jose Beltrán Jiménez, Tomi S. Koivisto

Thu - 12/19/24

**Title:

      Ekpyrosis in Quantum Gravitational Anisotropic Bouncing Models**  - **Authors:** Rachel Brown, A. Meenakshi McNamara, Sahil Saini, Parampreet Singh  - **Subjects:** Subjects: General Relativity and Quantum Cosmology (gr-qc); Cosmology and Nongalactic Astrophysics (astro-ph.CO)  - **Arxiv link:** [https://arxiv.org/abs/](https://arxiv.org/abs/)  - **Abstract**  We explore the isotropization of the universe starting from potentially large anisotropies in the bouncing models using the ekpyrotic mechanism. As an example of a concrete non-singular bouncing mechanism, we consider the effective description of loop quantum cosmology for Bianchi-I and Bianchi-IX spacetimes for ekpyrotic and ekpyrotic-like potentials. For both of these spacetimes the cosmological singularity is resolved via multiple short-duration non-singular bounces. We perform a large number of numerical simulations for a wide range of initial conditions and find that the relative strength of the anisotropies at the end of the bounce regime is noticeably reduced in more than $90\%$ of the simulations, providing strong evidence for the isotropization ability of the ekpyrotic potentials. While the ekpyrosis phase in all the simulations is found to be rather short-lived, isotropization occurs over cycles of rapid non-singular bounces in the Planck regime via enhancement of the contribution of the (isotropic) energy density relative to the anisotropies at the bounces. Achieving isotropization is found to be easier in Bianchi-I spacetimes when compared to Bianchi-IX spacetimes. Our results demonstrate that, while ekpyrosis might itself be insufficient to tame anisotropies at a single bounce, it can be significant when coupled with non-singular cycles in the bounce regime.

There is no new related paper today

Wed - 12/18/24

There is no new related paper today

There is no new related paper today

  1. [] - Title: Gravitational waves from regular black holes in extreme mass-ratio inspirals - Shailesh Kumar, Tieguang Zi

Tue - 12/17/24

**Title:

      An Exactly Soluble Group Field Theory**  - **Authors:** Luca Marchetti, Hassan Mehmood, Viqar Husain  - **Subjects:** Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)  - **Arxiv link:** [https://arxiv.org/abs/](https://arxiv.org/abs/)  - **Abstract**  We present a Group Field Theory (GFT) quantization of the Husain-Kuchař (HK) model formulated as a non-interacting GFT. We demonstrate that the path-integral formulation of this HK-GFT provides a completion of a corresponding spinfoam model developed earlier; we also show that the HK-GFT admits a unique Fock representation that describes the quantum three-geometries of the HK model. These results provide a link to the canonical quantization of the HK model and demonstrate how GFTs can bridge distinct quantization schemes.

**Title:

      An Exactly Soluble Group Field Theory**  - **Authors:** Luca Marchetti, Hassan Mehmood, Viqar Husain  - **Subjects:** Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)  - **Arxiv link:** [https://arxiv.org/abs/](https://arxiv.org/abs/)  - **Abstract**  We present a Group Field Theory (GFT) quantization of the Husain-Kuchař (HK) model formulated as a non-interacting GFT. We demonstrate that the path-integral formulation of this HK-GFT provides a completion of a corresponding spinfoam model developed earlier; we also show that the HK-GFT admits a unique Fock representation that describes the quantum three-geometries of the HK model. These results provide a link to the canonical quantization of the HK model and demonstrate how GFTs can bridge distinct quantization schemes.
  1. [] - Title: The Smarr formula within the Geroch-Held-Penrose formalism - Alberto Guilabert, Pedro Bargueño

Mon - 12/16/24

There is no new related paper today

There is no new related paper today

  1. [] - Title: Lectures in Quantum Gravity - Ivano Basile, Luca Buoninfante, Francesco Di Filippo, Benjamin Knorr, Alessia Platania, Anna Tokareva

New papers last week