Article
Astronomy & Astrophysics
N. Wanwieng, N. Chattrapiban, A. Watcharangkool
Summary: We investigate the influence of gravitational waves on a freely falling hydrogen atom by analyzing the dynamics of the bound electron described by the Dirac equation in the curved spacetime of a gravitational wave. We derive the corresponding Dirac Hamiltonian in the local inertial frame of the atom and employ the Foldy-Wouthuysen transformation to obtain a non-relativistic description. The analysis of interaction terms and comparison with flat spacetime counterparts provide valuable insights into the effects of gravitational waves on the hydrogen atom.
CLASSICAL AND QUANTUM GRAVITY
(2023)
Article
Astronomy & Astrophysics
Sukanta Panda, Abbas Tinwala, Archit Vidyarthi
Summary: This study employs the local momentum space technique to derive the first-order expansion of Feynman propagators for scalar field and graviton in the presence of background curvature. The obtained propagators are validated by comparing them with previous literature and traced heat kernel coefficients. These propagators are then utilized to calculate the one-loop divergences in the Vilkovisky-Dewitt's effective action for a scalar field non-minimally coupled with gravity in an arbitrary spacetime metric. The comparison between the VD effective action and the standard effective action reveals an important result regarding the limit kappa = 0 and the presence of gravity.
CLASSICAL AND QUANTUM GRAVITY
(2023)
Article
Physics, Particles & Fields
Michal Czakon, Felix Eschment, Tom Schellenberger
Summary: We elucidate the structure of the next-to-leading-power soft-gluon expansion of arbitrary one-loop massless-QCD amplitudes, and test it numerically on non-trivial processes. We evaluate the collinear-region contributions exactly for arbitrary processes, avoiding derivatives of process-dependent amplitudes in the collinear limit. Compared to previous studies, our analysis is more general and yields simpler formulas.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Physics, Particles & Fields
Sanjay Mandal, Sneha Pradhan, P. K. Sahoo, Tiberiu Harko
Summary: In this study, the properties of dark energy were explored using the modified f(Q) gravity theory. The model was tested against various observational datasets and shown to provide a convincing explanation for the accelerating expansion of the Universe.
EUROPEAN PHYSICAL JOURNAL C
(2023)
Article
Physics, Particles & Fields
Yoshihiko Abe, Tetsutaro Higaki, Junichiro Kawamura, Tatsuo Kobayashi
Summary: This study proposes models that utilize S'(4) modular flavor symmetry to explain the hierarchies of quark masses and mixing. The hierarchy is realized by stabilizing the modulus tau at Im tau >> 1, where the residual Z(4)(T) symmetry is approximately unbroken. The study finds that the quark hierarchies are only realized in certain cases of quark representations.
EUROPEAN PHYSICAL JOURNAL C
(2023)
Article
Physics, Particles & Fields
A. Ritchie-Yates, A. Deisting, G. Barker, S. Boyd, D. Brailsford, Z. Chen-Wishart, L. Cremonesi, P. Dunne, J. Eeles, P. Hamilton, A. C. Kaboth, N. Khan, A. Klustova, J. Monroe, J. Nowak, P. Singh, A. V. Waldron, J. Walding, L. Warsame, M. O. Wascko, I. Xiotidis
Summary: New measurements of neutrino-nucleus interactions are necessary for future neutrino experiments. A gas-filled time projection chamber (TPC) is an ideal detector, as it allows measurement of low-energy particles and increases neutrino interactions. This study evaluates the suitability of using multiwire proportional chambers (MWPCs) from the ALICE TPC as readout chambers in a high-pressure gas TPC. The successful operation of an ALICE TPC outer readout chamber (OROC) at high pressures is reported.
EUROPEAN PHYSICAL JOURNAL C
(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)
Article
Physics, Nuclear
Simone Cannarozzo, Stephan Pomp, Andreas Solders, Ali Al-Adili, Alf Gook, Arjan Koning
Summary: The level density models play an important role in the de-excitation process of nuclei and have implications on various aspects such as fission fragments, neutron and gamma-ray multiplicities, and isomeric states. In this study, six currently used level density models and the spin distribution were tested by comparing calculations with measured isomeric yield ratios. The results showed a clear preference for high-spin states in all six studied models. Further investigations indicated that reducing the width of the spin distribution significantly improves the agreement between calculated and experimentally observed yield ratios.
EUROPEAN PHYSICAL JOURNAL A
(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)
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
Physics, Nuclear
Yassid Ayyad, Adam K. Anthony, Daniel Bazin, Jie Chen, Gordon W. McCann, Wolfgang Mittig, Benjamin P. Kay, David K. Sharp, Juan Carlos Zamora
Summary: We discuss the reconstruction of low-energy nuclear reaction kinematics using charged-particle tracks in solenoidal spectrometers operating in Active Target Time Projection Chamber mode. An algorithm based on a linear quadratic estimator (Kalman filter) is employed to infer the reaction kinematics from the three dimensional point cloud. The performance of this algorithm is evaluated using experimental data from the Active Target Time Projection Chamber (AT-TPC) detector.
EUROPEAN PHYSICAL JOURNAL A
(2023)
