Article
Astronomy & Astrophysics
Daniel G. Figueroa, Adrien Florio, Francisco Torrenti, Wessel Valkenburg
Summary: In this paper, lattice techniques for simulating scalar and gauge field dynamics in an expanding universe are comprehensively discussed. The discretization of field theories, numerical algorithms, and lattice formulations for interacting scalar fields and gauge theories are presented. Symplectic integrators with different accuracy levels are provided for each case, along with relevant observables and constraints. The article also introduces the theoretical basis for the CosmoLattice code, a MPI-based package for simulating the non-linear evolution of field theories in an expanding universe.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Shao-Jiang Wang, Zi-Yan Yuwen
Summary: This paper proposes an iteration method that takes into account the variation of sound velocity across the bubble wall for a general and realistic equation of state (EoS) beyond the simple bag model and v-model. The study finds a suppression effect for the efficiency factor of bulk fluid motions, though it may be negligible for strong phase transitions.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Juan Garcia-Bellido, Hitoshi Murayama, Graham White
Summary: It has been suggested that Gaia has the potential to detect a stochastic gravitational wave background in a frequency range ideal for studying phase transitions in early universe cosmology. Additionally, Gaia could be used to differentiate between primordial black holes produced during early universe transitions and those expected from the QCD epoch. Furthermore, Gaia may play a role in exploring topological defects and shedding light on recent NANOGrav results.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
J. R. Espinosa, J. Huertas
Summary: The study found that the pseudo-bounce action is lower than the new instanton one, describing more faithfully the bottom of the action valley, covering a wider range of field space, and resulting in a decay rate that can be orders of magnitude lower than through new instantons.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Yilin Chen, Alexander Vilenkin
Summary: The process of pair production in a constant electric field is similar to bubble nucleation in a false vacuum. Each observer will still see nucleation to occur in its own rest frame, regardless of the motion of other observers. However, if the relative velocity of the two observers is high enough, particles and antiparticles of the pair can be observed moving towards each other with very large momenta, contrary to the usual expectation.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Thomas Biekoetter, Sven Heinemeyer, Jose Miguel No, Maria Olalla Olea-Romacho, Georg Weiglein
Summary: We analyze the thermal history of the 2HDM and find that the presence of vacuum trapping impedes a first-order electroweak phase transition in certain parameter regions. In the regions where the transition does occur, the parameter space for a detectable stochastic gravitational wave signal is constrained and will be well probed by the HL-LHC and measurements of the self-coupling of the Higgs boson at 125 GeV. The ILC has the ability to probe the majority of the 2HDM parameter space with high precision through measurements of the self-coupling.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Glauber C. Dorsch, Stephan J. Huber, Thomas Konstandin
Summary: This study re-evaluates the status of supersonic electroweak baryogenesis using a generalized fluid Ansatz for non-equilibrium distribution functions. By allowing for higher order terms and pointing out inconsistencies in standard treatments of transport, it suggests that baryogenesis may be possible even in the presence of supersonic wall velocities. The analysis supports recent findings and presents the first analysis of baryogenesis using the fluid approximation to higher orders.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Thomas Biekoetter, Sven Heinemeyer, Jose Miguel No, Maria Olalla Olea, Georg Weiglein
Summary: Extensions of the Higgs sector of the Standard Model can lead to a rich cosmological history around the electroweak scale, with the possibility of various phenomena such as non-restoration of electroweak symmetry or vacuum trapping. By focusing on the N2HDM of type II and considering theoretical and experimental constraints, scenarios of electroweak symmetry non-restoration, vacuum trapping, and first-order phase transition in the thermal history of the Universe are identified. Despite the presence of a global electroweak minimum in the scalar potential at zero temperature, the physical viability of the N2HDM parameter space is not guaranteed, emphasizing the importance of analyzing tunneling probability for reliable predictions of the Universe's thermal history.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Rong-Gen Cai, Shao-Jiang Wang
Summary: Recent calculations on thermal friction on an expanding bubble from the cosmic first-order phase transition have revealed higher-order friction effects, leading to a proposed effective equation of motion for bubble wall expansion. The gamma(2)-scaling friction in bubble collisions results in a slightly larger signal of gravitational waves background.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Kiyoharu Kawana, Philip Lu, Ke-Pan Xie
Summary: The remnants of false vacuum in the early Universe can potentially serve as dark matter, forming compact objects such as primordial black holes, Fermi-balls, Q-balls or thermal balls. These remnants are formed due to the large mass gaps between different phases and can exist over a broad mass range. Notably, thermal balls in the dark sector can retain high temperatures and derive their energy from internal particles' thermal energy instead of their mass or quantum pressure.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Kimmo Kainulainen
Summary: In this study, CP-violating transport equations for fermions in electroweak baryogenesis are derived from the CTP formalism with thermal corrections at the one-loop level. It is found that the VIA method leads to ill-defined source terms due to an assumption, while the SC method accurately reproduces current divergence equations and captures semiclassical source terms effectively. The results also show that both VIA and collisional source terms reported in previous literature are ambiguous and vanish in a consistent calculation.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Edmund J. Copeland, Peter Millington, Sergio Sevillano Munoz
Summary: We study the origin of fifth forces in scalar-tensor theories of gravity in the Jordan frame and find that a kinetic mixing between the non-minimally coupled scalar field and the graviton can give rise to such forces between matter fields.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Peter Athron, Csaba Balazs, Lachlan Morris
Summary: We investigate rarely explored details of supercooled cosmological first-order phase transitions at the electroweak scale, which may lead to strong gravitational wave signals or explain the cosmic baryon asymmetry. We argue that the nucleation temperature is not fundamental or essential in phase transition analysis and provide empirical bounds on the bubble wall velocity for the completion of a transition. We also propose the use of percolation temperature as a reference temperature for gravitational wave production.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Glauber C. Dorsch, Stephan J. Huber, Thomas Konstandin
Summary: This paper revisits the computation of bubble wall friction during a cosmological first-order phase transition and solves the linearized Boltzmann equation using an extended fluid ansatz. A singularity is discovered in the fluctuations of background species as the wall approaches the speed of sound. By using hydrodynamics, it is argued that a discontinuity across the speed of sound is expected and manifests itself as the singularity in the solution of the linearized system. This result is discussed in comparison with alternative approaches, which find a regular behavior of the friction for all velocities.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Shyam Balaji, Michael Spannowsky, Carlos Tamarit
Summary: In first-order cosmological phase transitions, subluminal bubble expansion requires out-of-equilibrium interactions with the plasma, which can be understood from the conservation of entropy in local equilibrium, leading to subluminal speeds for both deflagrations and detonations. Friction effect arises from the background field dependence of the entropy density in the plasma, and can be accounted for by imposing local conservation of stress-energy and including field-dependent thermal contributions to the effective potential. Illustrative calculations for a first-order electroweak transition in a Standard Model extension with additional scalar fields demonstrate these effects.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Physics, Particles & Fields
Tobias Binder, Kyohei Mukaida, Bruno Scheihing-Hitschfeld, Xiaojun Yao
Summary: This article presents a complete next-to-leading order calculation of the non-Abelian electric field correlator in a SU(N-c) plasma, providing insights into the properties of the plasma that are relevant for heavy particle bound state formation and dissociation.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Yohei Ema, Kyohei Mukaida, Kazunori Nakayama
Summary: The hidden sector scalar field generically couples to quadratic curvature through dimension five operators, potentially inducing decays into graviton pairs. Decay of the scalar field can produce a significant amount of stochastic cosmic graviton background at high frequencies due to the suppression scale being determined by the mass of heavy particles rather than the Planck scale. The resulting graviton spectrum is computed in specific models, highlighting the phenomenological interest of these scalar couplings.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Multidisciplinary
Kyohei Mukaida, Kai Schmitz, Masaki Yamada
Summary: Charged-lepton flavor violation (CLFV) is a distinct feature of physics beyond the standard model, which plays an important role in the early universe. This Letter points out that efficient CLFV interactions create new pathways for generating the baryon asymmetry of the universe, and the conversion factor from lepton flavor asymmetry to baryon asymmetry is naturally explained by the suppression of charged-lepton Yukawa couplings squared.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Particles & Fields
Kyohei Mukaida, Masaki Yamada
Summary: This paper investigates the thermalization of high-energy standard model particles in thermal plasma, considering the Landau-Pomeranchuk-Migdal effect. The distribution function of each particle species is calculated numerically and analytically. The results demonstrate that, after multiple splittings, the particle distributions converge to certain values at low momentum, independent of the high-energy particles injected by inflaton decay. This is helpful for calculating the dark matter abundance produced during the pre-thermal phase.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Valerie Domcke, Keisuke Harigaya, Kyohei Mukaida
Summary: We study the transfer of charge between complex scalar fields and find that under certain conditions, this transfer can be very efficient. This has important implications for cosmological studies involving complex scalar fields.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Astronomy & Astrophysics
Minxi He, Kazunori Kohri, Kyohei Mukaida, Masaki Yamada
Summary: This paper investigates the thermalization of Hawking radiation from primordial black holes in the early Universe, taking into account the interference effect on thermalization of high energy particles. The findings show that small primordial black holes completely evaporate before the big bang nucleosynthesis, and the radiation emitted from these black holes results in a hot spot with a non-trivial temperature profile around them.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Tomohiro Fujita, Kyohei Mukaida, Yuichiro Tada
Summary: In this study, we develop a stochastic formalism for U(1) gauge fields coupled with a rolling pseudo-scalar field during inflation. We derive the Langevin equations for the physical electromagnetic fields and study their analytic solutions. Through numerical simulation, we demonstrate that the averaged electromagnetic fields over the Hubble scale continuously change their direction and fluctuate around the analytically obtained expectation values. While the isotropy is spontaneously broken in each local Hubble patch, it is globally preserved by averaging all the Hubble patches.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Physics, Particles & Fields
Valerie Domcke, Yohei Ema, Kyohei Mukaida
Summary: This paper investigates the problem of particle production in a time-dependent background, focusing on the transient effects of fermions in a homogeneous axion background. The definition of particles and antiparticles at intermediate times in the presence of external fields is more ambiguous compared to the asymptotic states in conventional cases, and these external fields also lead to divergences that require regularization.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Valerie Domcke, Kohei Kamada, Kyohei Mukaida, Kai Schmitz, Masaki Yamada
Summary: CP violations and B-L violations are not required to occur simultaneously for successful leptogenesis. New CP-violating interactions at high energies can result in primordial charge asymmetries, which can then be transformed into a nonvanishing B-L asymmetry by right-handed neutrinos at lower energies. In this paper, we study a novel mechanism known as wash-in leptogenesis, using axion inflation as the source of high-scale CP violation. We find a large range of viable scenarios and provide insights into intergalactic magnetic fields, primordial black holes, and gravitational waves.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Astronomy & Astrophysics
Masaki Yamada, Kazuya Yonekura
Summary: We discuss the formation of cosmic strings or macroscopic color flux tubes after the deconfinement/con-finement phase transition in the pure Yang-Mills theory. These cosmic strings, based on holographic dual descriptions, can be interpreted as F-strings or D-strings in the gravity side, depending on the structure of the gauge group. The reconnection probabilities of F- and D-strings are suppressed by factors of 1/N^2 and e^-cN, respectively, in the large-N limit. The formation of color flux tubes after the phase transition is similar to the formation of local cosmic strings after spontaneous symmetry breaking in the weak-U(1) gauge theory. We use a velocity-dependent one-scale model to describe the dynamics of the string network and calculate the gravitational wave signals from string loops, considering the dependence on the size of produced string loops.
Article
Astronomy & Astrophysics
Shota Nakagawa, Fuminobu Takahashi, Masaki Yamada, Wen Yin
Summary: This study investigates the behavior of an axion-like particle (ALP) that goes through a first-order phase transition in terms of its mass or potential minimum. It is observed that if the ALP obtains a potential from non-perturbative effects of SU(N) gauge theory confined via the first-order phase transition, similar dynamics can be achieved as in the trapped misalignment mechanism. The enhanced ALP abundance in this mechanism provides an explanation for dark matter and is accessible to experiments such as IAXO, ALPS-II, and DM-radio.
Article
Physics, Multidisciplinary
Valerie Domcke, Kohei Kamada, Kyohei Mukaida, Kai Schmitz, Masaki Yamada
Summary: This letter investigates the relationship between helical hypermagnetic fields and fermion asymmetry in the early Universe caused by chiral chemical potential. The study demonstrates that even with zero total lepton number, a mechanism can be triggered through lepton flavor asymmetry. This sets a constraint on lepton flavor asymmetry at temperatures above 106 GeV, which is about two orders of magnitude stronger than current limits from cosmic microwave background and primordial nucleosynthesis.
PHYSICAL REVIEW LETTERS
(2023)
Article
Physics, Particles & Fields
Masaki Yamada, Kazuya Yonekura
Summary: We propose a candidate for dark matter (DM) in the form of a baryonic glueball, which is a stable and naturally produced type of glueball in the SO(2N) pure Yang-Mills theory. This model offers characteristic gravitational wave signals for testing and can explain both the abundance of DM and the recently detected gravitational wave signals.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Astronomy & Astrophysics
Masaki Yamada, Kazuya Yonekura
Summary: This study discusses the formation of cosmic strings or macroscopic color flux tubes in the phase transition from the deconfinement to confinement phase in pure Yang-Mills theory. The holographic dual descriptions suggest that the cosmic strings are related to fundamental strings or wrapped D-branes in gravity side, with reconnection probability being suppressed. The study shows that the pure YM theory provides a simple realization of cosmic F-and D-strings.
