Article
Astronomy & Astrophysics
Mustafa A. Amin, Zong-Gang Mou
Summary: The study focuses on investigating the bursts of electromagnetic and scalar radiation resulting from the collision and merger of oscillons made from axion-like particles. It is found that radiation becomes the dominant source of energy loss after the merger under resonance condition. The backreaction of scalar and electromagnetic radiation is also included in the simulations, providing insights into the time and energy scales involved in the process.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Masahiro Kawasaki, Wakutaka Nakano, Hiromasa Nakatsuka, Eisuke Sonomoto
Summary: In this paper, the oscillons of the pure-natural type potential are investigated through classical lattice simulation to explore key quantities necessary for phenomenological application, such as the number density of oscillons and their mass distribution.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Hong-Yi Zhang, Mudit Jain, Mustafa A. Amin
Summary: This paper demonstrates the existence of vector oscillons in the low-energy effective theory of an interacting massive vector field. Two types of vector oscillons are provided, with vanishing orbital angular momentum and approximately spherically symmetric energy density.
Article
Physics, Multidisciplinary
Natascha Hedrich, Kai Wagner, Oleksandr V. Pylypovskyi, Brendan J. Shields, Tobias Kosub, Denis D. Sheka, Denys Makarov, Patrick Maletinsky
Summary: The study demonstrated manipulation and interaction of antiferromagnetic domain walls using isolated 180 degree domain walls in a single crystal of Cr2O3, proposing a memory architecture based on topographically defined antiferromagnetic domain walls. These results advance the understanding of domain wall mechanics in antiferromagnets.
Article
Astronomy & Astrophysics
Fabio van Dissel, Evangelos I. Sfakianakis
Summary: This study focuses on oscillons made up of multiple interacting fields and explores their stability and shape through analytical and numerical techniques. The research shows that unstable oscillons can either completely disperse or relax to the closest stable configuration, with stability being influenced by the initial perturbation size.
Article
Chemistry, Multidisciplinary
Zijian Hong, Sujit Das, Christopher Nelson, Ajay Yadav, Yongjun Wu, Javier Junquera, Long-Qing Chen, Lane W. Martin, Ramamoorthy Ramesh
Summary: Controlling domain formation in ferroelectric materials at the nanoscale is crucial for exploring emergent phenomena and technological prospects. Polar vortices can play a similar role as ferroelectric domain walls, but with the ability to accommodate charged domains, making them reversible under an external applied field.
Article
Astronomy & Astrophysics
T. S. Mendonca, H. P. de Oliveira
Summary: In this work, the consequences of higher-order field theories on oscillons have been examined. It has been found that by using a generalization of the symmetric double-well potential and a 06 potential, 3 + 1 spherically symmetric oscillons with significantly large lifetimes can be obtained without parameter fine-tuning.
Article
Astronomy & Astrophysics
Francesco Bigazzi, Aldo L. Cotrone, Andrea Olzi
Summary: When axionic strings carry a global charge, domain walls bounded by such strings may not be allowed to decay completely. This happens in particular in some models where a composite axionlike particle is the pseudo-Nambu-Goldstone boson of chiral symmetry breaking of an extra quark flavor. In this case, the global symmetry is the extra flavor baryonic symmetry. The corresponding axionic domain walls can carry a baryonic charge: they represent the low energy description of the baryons made by the extra quark flavor. Basic properties of these particles, such as spin, mass scale, and size are discussed. The corresponding charged axionic strings are explicitly constructed in a specific calculable model.
Article
Materials Science, Ceramics
Mojca Otonicar, Mirela Dragomir, Tadej Rojac
Summary: This article highlights the importance of domain walls in ferroelectric and relaxor-based oxide ceramics and discusses their impact on material properties. By studying the dynamics of domain walls, insights into the design and application of these materials can be gained.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2022)
Article
Astronomy & Astrophysics
Yi-Jie Wang, Qi-Xin Xie, Shuang-Yong Zhou
Summary: In this study, we investigate two types of excited oscillons. We first focus on oscillons with spherical symmetry and find a tower of spherical oscillons with higher energies. Despite having multiple approximate nodes in their energy density profiles, these oscillons have long lifetimes. We also discover excited oscillons with higher approximate multipoles, which generally have shorter lifespans than the spherical ones.
Article
Physics, Multidisciplinary
Kaloian D. Lozanov, Volodymyr Takhistov
Summary: In broad classes of inflationary models, rapid decay of localized oscillon excitations significantly enhances the primordial gravitational wave (GW) spectrum. These oscillon-induced GWs, sourced by second-order perturbations, could have lower frequency than previously considered GWs associated with oscillon formation. Detectable oscillon-induced GW signatures offer direct tests for regions of parameter space of various inflationary models. Observing oscillon-induced GWs in a model based on pure natural inflation is possible with current gravitational wave detectors. These signatures provide a new route for probing the underlying inflationary physics.
PHYSICAL REVIEW LETTERS
(2023)
Article
Astronomy & Astrophysics
D. G. Levkov, V. E. Maslov
Summary: This study provides a precise analytic description of oscillons in scalar field theories with nearly quadratic potentials. It introduces a method based on expanding the anharmonicity of the potential and introducing a field-dependent running mass, and computes the effective action for the oscillon profile and other parameters. Comparison with numerical simulations shows that this method is more accurate than other analytic approaches.
Article
Multidisciplinary Sciences
Sonka Reimers, Dominik Kriegner, Olena Gomonay, Dina Carbone, Filip Krizek, Vit Novak, Richard P. Campion, Francesco Maccherozzi, Alexander Bjorling, Oliver J. Amin, Luke X. Barton, Stuart F. Poole, Khalid A. Omari, Jan Michalicka, Ondrej Man, Jairo Sinova, Tomas Jungwirth, Peter Wadley, Sarnjeet S. Dhesi, Kevin W. Edmonds
Summary: This study reveals that the antiferromagnetic (AF) domain structure in CuMnAs thin films is dominated by nanoscale structural twin defects, which play a crucial role in determining the location and orientation of AF domain walls. The results provide insights into the interplay of crystalline defects, strain, and magnetic ordering in AF materials, offering a route to optimize device performance.
NATURE COMMUNICATIONS
(2022)
Review
Engineering, Mechanical
R. A. Ibrahim
Summary: This article discusses various fluid motion phenomena, including oscillons, rogue waves, localized standing surface waves, and droplet motion on Faraday waves. The characteristics and behaviors of these phenomena in different environments are explored in the article.
NONLINEAR DYNAMICS
(2021)
Article
Chemistry, Multidisciplinary
Yurii Tikhonov, Jesi R. Maguire, Conor J. McCluskey, James P. McConville, Amit Kumar, Haidong Lu, Dennis Meier, Anna Razumnaya, John Martin Gregg, Alexei Gruverman, Valerii M. Vinokur, Igor Luk'yanchuk
Summary: Ferroelectric domain walls play an important role in novel materials physics, where polarization discontinuities often lead to emergent 2D conductivity. In multiaxial ferroelectrics, complex topological patterns can ameliorate such discontinuities, while in uniaxial ferroelectrics, discontinuities are assumed to be unavoidable. However, experimental and theoretical investigations on lead germanate reveal that polar discontinuities can be obviated by mutual domain bifurcation along different axes, creating a characteristic saddle-point domain wall morphology and associated novel dipolar topology.
ADVANCED MATERIALS
(2022)
Article
Physics, Multidisciplinary
Daniel Cutting, Mark Hindmarsh, David J. Weir
PHYSICAL REVIEW LETTERS
(2020)
Article
Physics, Particles & Fields
Feanor Reuben Ares, Mark Hindmarsh, Carlos Hoyos, Niko Jokela
Summary: Investigating first order phase transitions in a holographic setting, we explore the parameter space and physical quantities, finding a strong correlation between alpha and stiffness. We propose the potential observation of a TeV-scale hidden sector at future space-based detectors using a corrected gravitational wave power spectrum model.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Astronomy & Astrophysics
Chloe Gowling, Mark Hindmarsh
Summary: This study investigates LISA's sensitivity to the thermodynamic parameters encoded in the stochastic background produced by a phase transition using the sound shell model to characterize the gravitational wave power spectrum and the Fisher matrix to estimate uncertainties. The power spectrum in the sound shell model can be well approximated by a four-parameter double broken power law, and the peak power and frequency can be measured to approximately 10% accuracy for signal-to-noise ratios (SNRs) above 20. The phase boundary speed is found to be the best constrained parameter, with potential for good prospects in combinations of parameters.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Review
Physics, Particles & Fields
Nancy Aggarwal, Odylio D. Aguiar, Andreas Bauswein, Giancarlo Cella, Sebastian Clesse, Adrian Michael Cruise, Valerie Domcke, Daniel G. Figueroa, Andrew Geraci, Maxim Goryachev, Hartmut Grote, Mark Hindmarsh, Francesco Muia, Nikhil Mukund, David Ottaway, Marco Peloso, Fernando Quevedo, Angelo Ricciardone, Jessica Steinlechner, Sebastian Steinlechner, Sichun Sun, Michael E. Tobar, Francisco Torrenti, Caner Unal, Graham White
Summary: The white paper outlines the challenges and gains expected in gravitational-wave searches, focusing on Ultra High-Frequency Gravitational Waves (UHF-GWs). The absence of known astrophysical sources in the UHF-GWs frequency range provides a unique opportunity to discover physics beyond the Standard Model. The report is a summary of a workshop held at ICTP Trieste, Italy, which set the stage for the Ultra-High-Frequency Gravitational Wave (UHF-GW) initiative.
LIVING REVIEWS IN RELATIVITY
(2021)
Article
Physics, Multidisciplinary
Feanor Reuben Ares, Oscar Henriksson, Mark Hindmarsh, Carlos Hoyos, Niko Jokela
Summary: Using a holographic derivation method, we compute quasiequilibrium parameters for the gravitational wave signal from a first-order phase transition in a simple dual model. We discuss how these parameters vary with the effective degrees of freedom of the dual field theory. If the critical temperature is around a TeV and the field theory exhibits approximate conformal symmetry, our model can produce an observable signal at LISA.
PHYSICAL REVIEW LETTERS
(2022)
Article
Astronomy & Astrophysics
Pierre Auclair, Chiara Caprini, Daniel Cutting, Mark Hindmarsh, Kari Rummukainen, Daniele A. Steer, David J. Weir
Summary: In this study, we investigate the stochastic gravitational wave background (SGWB) produced by freely decaying vortical turbulence in the early Universe. We use hydrodynamical simulations and a Monte Carlo algorithm to study the time correlation of the velocity field and derive a new model for the turbulent velocity field consistent with the simulations. Furthermore, we analyze the UETC and propose the use of the Gibbs kernel to ensure the positive definiteness of the SGWB. The results from the numerical integration and simulations show close agreement, and we provide an approximate analytical form for the SGWB spectrum and its scaling with the initial kinetic energy and integral scale. Additionally, we demonstrate that including an initial growth phase for the turbulent flow heavily influences the spectral shape of the SGWB.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Multidisciplinary Sciences
Y. Tian, D. Lotnyk, A. Eyal, K. Zhang, N. Zhelev, T. S. Abhilash, A. Chavez, E. N. Smith, M. Hindmarsh, J. Saunders, E. Mueller, J. M. Parpia
Summary: Due to its extreme purity, lack of disorder, and complex order parameter, the first-order superfluid He-3 A-B transition is considered as a leading model system for first order transitions in the early universe. In this study, the path dependence of the supercooling of the A phase is reported over a wide range of pressures below 29.3 bar at nearly zero magnetic field. It is found that the metastability of the A phase is enhanced by transiting through regions where the A phase is more stable, resulting in additional supercooling due to the elimination of B phase nucleation precursors formed upon passage through the superfluid transition.
NATURE COMMUNICATIONS
(2023)
Article
Astronomy & Astrophysics
Chloe Gowling, Mark Hindmarsh, Deanna C. Hooper, Jesus Torrado
Summary: In this paper, a method for investigating LISA's sensitivity to gravitational waves from a first order phase transition using parametrised templates is introduced and tested. The motivation for developing the method is to provide a less computationally intensive way to perform Markov Chain Monte Carlo (MCMC) inference on the thermodynamic parameters of a first order phase transition. The reconstruction method substantially reduces the proposal evaluation time and is cost-effective overall.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Mark Hindmarsh, Jun'ya Kume
Summary: Large-scale numerical solutions show that Nielsen-Olesen vortices in the Abelian-Higgs model can behave like Nambu-Goto strings with a dominant decay channel into gravitational radiation. This indicates that cosmic strings can be sources of both high-energy particles and gravitational waves.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Guillaume Boileau, Nelson Christensen, Chloe Gowling, Mark Hindmarsh, Renate Meyer
Summary: This study examines the possibility of detecting a gravitational-wave background from first order phase transitions in the early universe using the Laser Interferometer Space Antenna (LISA). It explores the effects of extragalactic and galactic foregrounds, as well as LISA noise, on the observation. The researchers find that LISA has the potential to detect the gravitational-wave background and accurately estimate its parameters.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Jani Dahl, Mark Hindmarsh, Kari Rummukainen, David J. Weir
Summary: This study investigates decaying acoustic turbulence and finds a self-similar broken power law in its energy spectrum. The results provide a more accurate prediction of the gravitational wave power spectrum for early universe phase transition scenarios.
Article
Astronomy & Astrophysics
Mudhahir Al Ajmi, Mark Hindmarsh
Summary: The passage discusses a key observable in the gravitational wave power spectrum from a first order phase transition in the early Universe, which is the mean bubble spacing. It also explains that the expansion of bubbles as deflagrations can affect the gravitational wave signal.
Article
Astronomy & Astrophysics
Feanor Reuben Ares, Oscar Henriksson, Mark Hindmarsh, Carlos Hoyos, Niko Jokela
Summary: In this paper, we discuss the computation of the quantum effective action for strongly interacting field theories using holographic duality, and its application in determining the quasiequilibrium parameters of first-order phase transitions relevant for gravitational wave production. We introduce a simple holographic model that includes only the metric and a free massive scalar field. Despite its simplicity, the model exhibits a rich phase diagram with first-order phase transitions at nonzero temperature due to various multitrace deformations. By studying homogeneous black brane solutions and linearized perturbations, we obtain the leading terms in the effective action. We then use the effective action to construct bubble and domain wall solutions in the field theory and investigate their properties, particularly how the scaling of the effective action with the effective number of degrees of freedom determines the scaling of gravitational wave parameters.
Article
Astronomy & Astrophysics
Mark Hindmarsh, Joanes Lizarraga, Ander Urio, Jon Urrestilla
Summary: The study found that in the Abelian-Higgs model, loops formed by intersections of infinite strings from random-field initial conditions disappear quickly, with lifetimes proportional to their initial rest-frame length. However, oscillating nonself intersecting loops constructed using a new method have lifetimes scaling differently. The study also shows differences in mean-square velocity and proposes a parameter to quantify uncertainty in loop survival.
Article
Astronomy & Astrophysics
Mark Hindmarsh, Joanes Lizarraga, Asier Lopez-Eiguren, Jon Urrestilla
Summary: The study reveals that scaling in axion string networks in the radiation era can be well described by a two-parameter velocity-one-scale (VOS) model, with the parameters being insensitive to the initial state of the network. The simulations, even starting far from the fixed point, are accounted for by the VOS model with certain values for the parameters.
