Article
Astronomy & Astrophysics
G. A. Contrera, J. P. Carlomagno, A. G. Grunfeld
Summary: In this work, we used a nonlocal NJL model to investigate various aspects of the phase diagram by considering the effects of temperature and neutrino trapping in compact object configurations.
ASTRONOMISCHE NACHRICHTEN
(2023)
Article
Astronomy & Astrophysics
Truong Xuan Pham
Summary: This paper establishes the constructions of conformal scattering theories for tensorial wave equations on Schwarzschild spacetime. The method combines Penrose's conformal compactification and the energy decay results of tensorial fields to prove the energy equality of the fields through the conformal boundary and the initial Cauchy hypersurface. The well-posedness of the Goursat problem is proven using a generalization of Hörmander's results.
CLASSICAL AND QUANTUM GRAVITY
(2023)
Article
Astronomy & Astrophysics
A. A. Araujo Filho, J. Furtado, J. A. A. S. Reis, J. E. G. Silva
Summary: This work analyzes the thermodynamic properties of non-interacting particles under the influence of the gravitational field of a traversable wormhole. The study investigates how the thermodynamic quantities are affected by the Ellis wormhole geometry in three different regions. The results show that the thermodynamic state quantities exhibit significant changes by varying the parameter controlling the wormhole throat radius, displaying behaviors similar to both usual matter and dark energy. Additionally, the interactions seem to have the potential to cure the dark energy-like features.
CLASSICAL AND QUANTUM GRAVITY
(2023)
Correction
Astronomy & Astrophysics
Oscar Castillo-Felisola, Bastian Grez, Oscar Orellana, Jose Perdiguero, Aureliano Skirzewski, Alfonso R. Zerwekh
CLASSICAL AND QUANTUM GRAVITY
(2023)
Correction
Astronomy & Astrophysics
Ulrich K. Beckering Vinckers, Alvaro de la Cruz-Dombriz, Denis Pollney
CLASSICAL AND QUANTUM GRAVITY
(2023)
Article
Astronomy & Astrophysics
A. Mikovic
Summary: By studying the convergence of the path integral, we have shown that it is possible to construct a finite quantum gravity theory on a piecewise linear spacetime that yields classical general relativity coupled to the standard model.
CLASSICAL AND QUANTUM GRAVITY
(2023)
Article
Astronomy & Astrophysics
F. D. Lora-Clavijo, G. D. Prada-Mendez, L. M. Becerra, E. A. Becerra-Vergara
Summary: This work investigates the possibility of a naked singularity at the center of the Milky Way and provides evidence supporting the idea through data fitting and shadow observation.
CLASSICAL AND QUANTUM GRAVITY
(2023)
Correction
Astronomy & Astrophysics
James Healy, Carlos O. Lousto, Hiroyuki Nakano, Yosef Zlochower
CLASSICAL AND QUANTUM GRAVITY
(2023)
Article
Astronomy & Astrophysics
Mariela Masso Reid, Karen Haughian, Alan Cumming, James Faller, Giles Hammond, James Hough, Anna-Maria van Veggel, Sheila Rowan
Summary: This paper investigates the thermal conductivity of hydroxide catalysis bonds in gravitational wave detectors and concludes that the use of hydroxide catalysis bonding has minimal impact on the required heat extraction for cryogenic operation. Therefore, it remains an attractive solution for building future cryogenic instruments with reduced thermal noise and enhanced astrophysical reach.
CLASSICAL AND QUANTUM GRAVITY
(2023)
Article
Astronomy & Astrophysics
T. Thiemann
Summary: This paper demonstrates the exact quantization of the U(1)(3) model and shows that the quantum constraints can be solved precisely using groupoid averaging. The solution serves as an ideal testing ground for general spin foam models.
CLASSICAL AND QUANTUM GRAVITY
(2023)
Article
Astronomy & Astrophysics
Adam J. Peterson, Don Willcox, Philipp Mosta
Summary: This article presents a new code generator based on python/SymPy for producing executable numerical expressions to solve partial differential equations. The generator is applied to the constraint damped and conformal Z4 formulations in 3+1 ADM numerical relativity. The generated solvers are tested for stability and accuracy and applied to physically interesting vacuum spacetimes and gravitational waveforms.
CLASSICAL AND QUANTUM GRAVITY
(2023)
Article
Astronomy & Astrophysics
Wentong Fan, Sijun Fang, Hongwen Hai, Jie Song, Jinhang Zhou, Yuwei Wu, Rurui Zou, Kai Zhao, Rui Zhang, Bohong Li, Jian Luo, Bin He, Minyan Qiu, Lei Fan, Zizheng Li, Hongchao Zhao, Yong Yan
Summary: This paper establishes a computational analysis model and proposes a method to reduce the internal TTL coupling noise of the telescope. By optimizing the telescope optical system, the non-geometric TTL coupling noise has been successfully reduced, providing guidance for the design of telescopes with low coupling noise.
CLASSICAL AND QUANTUM GRAVITY
(2023)
Article
Astronomy & Astrophysics
Jonah S. Peter, Tom A. Nordheim, Kevin P. Hand
Summary: The Cassini spacecraft observed jets erupting from Saturn's moon Enceladus, containing compounds such as H2O, CO2, CH4, NH3, and H2. By using statistical analysis and low-velocity INMS data, additional compounds like HCN, C2H2, C3H6, and C2H6 were detected. These compounds, along with mineral catalysts and redox gradients, could support microbial communities and organic synthesis leading to the origin of life.
Review
Astronomy & Astrophysics
Leonardo Abbrescia, Jared Speck
Summary: In this article, supplementary notes on the lectures about relativistic Euler equations and shocks are provided. The focus is on the analysis of shock formation in one and three spatial dimensions, the mathematical theory of shock waves, and the discussion of open problems related to shocks.
CLASSICAL AND QUANTUM GRAVITY
(2023)
Article
Astronomy & Astrophysics
Elisa Robert, Mathieu Barthelemy, Gael Cessateur, Angelique Woelffle, Herve Lamy, Simon Bouriat, Magnar Gullikstad Johnsen, Urban Brandstrom, Lionel Biree
Summary: We present an innovative method to reconstruct the characteristics of precipitated electrons in auroral regions from optical measurements. This study shows that the energy flux is linked to the column integrated intensity, the mean energy is linked with the peak altitude of the emission, and the width of the energy distribution with the altitude thickness of the emissions.
JOURNAL OF SPACE WEATHER AND SPACE CLIMATE
(2023)
Article
Astronomy & Astrophysics
Peter O. Hess, Fridolin Weber, Benno Bodmann, Jose de Freitas Pacheco, Dimiter Hadjimichef, Marcelo Netz-Marzola, Geovane Naysinger, Moises Razeira, Cesar A. Zen Vasconcellos
Summary: This article discusses the implications of a noncommutative formulation of branch-cut quantum gravity, exploring the evolution of the Universe's wave function using a mini-superspace structure that follows the noncommutative Poisson algebra and the Horava-Lifshitz quantum gravity. The study incorporates a scalar inflaton field and investigates various inflationary models, obtaining solutions to the wave equations without the need for numerical approximations. The results suggest that the noncommutative algebraic space captures both low and high spacetime scales, driving the exponential acceleration of the Universe.
ASTRONOMISCHE NACHRICHTEN
(2023)
Article
Astronomy & Astrophysics
Fridolin Weber, Peter O. Hess, Benno Bodmann, Jose de Freitas Pacheco, Dimiter Hadjimichef, Marcelo Marzola, Geovane Naysinger, Moises Razeira, Cesar A. Zen Vasconcellos
Summary: This paper focuses on the implications of a commutative formulation that integrates branch-cutting cosmology, the Wheeler-DeWitt equation, and Horava-Lifshitz quantum gravity. It explores the impact of branch-cut gravity and scalar fields on the wave function of the Universe, revealing a unique spacetime structure.
ASTRONOMISCHE NACHRICHTEN
(2023)
Article
Astronomy & Astrophysics
Tom Richtler, Ricardo Salinas, Richard Lane, Michael Hilker
Summary: This study investigates the dynamics of isolated elliptical galaxies and explores models without dark matter or MOND. By using globular clusters and galaxy light as tracers, the mass profile of the galaxy is constrained. The study finds evidence for a disturbed velocity field and constructs models for galaxy light and globular cluster mass estimators, which show that MOND is compatible with the mass distribution but a dark matter-free galaxy cannot be excluded.
ASTRONOMISCHE NACHRICHTEN
(2023)
Article
Astronomy & Astrophysics
Fridolin Weber, Peter O. Hess, Benno Bodmann, Jose de Freitas Pacheco, Dimiter Hadjimichef, Marcelo Marzola, Geovane Naysinger, Moises Razeira, Cesar A. Zen Vasconcellos
Summary: This article explores the implications of the commutative formulation based on branch-cutting cosmology, the Wheeler-DeWitt equation, and Horava-Lifshitz quantum gravity on the evolution of the Universe. By studying the impact of a scalar field phi(t) on the trajectory of the scale factor, it is found that the branch-cut Universe exhibits diverse evolutionary behaviors and can overcome the big bang and big crunch singularities.
ASTRONOMISCHE NACHRICHTEN
(2023)
Article
Astronomy & Astrophysics
Cheryl Henkels
Summary: The exclusive photo- and electroproduction of light vector mesons were studied using color dipole formalism with vector meson wave functions obtained using the AdS/QCD holographic approach. The results show significant theoretical uncertainties related to modeling the partial dipole amplitude, which can be constrained with upcoming measurements in future hadron colliders.
ASTRONOMISCHE NACHRICHTEN
(2023)
