A5036831233- Cosmology and Gravitation Theories
- Particle physics theoretical and experimental studies
- Black Holes and Theoretical Physics
- Pulsars and Gravitational Waves Research
- Dark Matter and Cosmic Phenomena
- Galaxies: Formation, Evolution, Phenomena
- Quantum Chromodynamics and Particle Interactions
- Computational Physics and Python Applications
- Neutrino Physics Research
- Quantum, superfluid, helium dynamics
- Radio Astronomy Observations and Technology
- Astrophysics and Cosmic Phenomena
- Cold Atom Physics and Bose-Einstein Condensates
- Scientific Research and Discoveries
- Atomic and Subatomic Physics Research
- High-Energy Particle Collisions Research
- Geophysics and Gravity Measurements
- Stochastic processes and financial applications
- Physics of Superconductivity and Magnetism
- Solar and Space Plasma Dynamics
- Advanced Thermodynamics and Statistical Mechanics
- Astronomy and Astrophysical Research
- Gamma-ray bursts and supernovae
- Theoretical and Computational Physics
- Complex Systems and Time Series Analysis
Deutsches Elektronen-Synchrotron DESY
2013-2024
Hamburg Institut (Germany)
2017
European Organization for Nuclear Research
2010-2012
Universitat Autònoma de Barcelona
2008-2010
Institute for High Energy Physics
2008-2010
AlbaNova
2006-2008
KTH Royal Institute of Technology
2006-2008
Heidelberg Institute for Theoretical Studies
2003-2005
Heidelberg University
2002-2005
We investigate the potential for eLISA space-based interferometer to detect stochastic gravitational wave background produced by strong first-order cosmological phase transitions. discuss resulting contributions from bubble collisions, magnetohydrodynamic turbulence, and sound waves background, estimate total corresponding signal predicted in waves. The projected sensitivity of transitions is computed a model-independent way various detector designs configurations. By applying these results...
The study of the hydrodynamics bubble growth in first-order phase transitions is very relevant for electroweak baryogenesis, as baryon asymmetry depends sensitively on wall velocity, and also predicting size gravity wave signal resulting from collisions, which both velocity plasma fluid velocity. We perform such different expansion regimes, namely deflagrations, detonations, hybrids (steady states) runaway solutions (accelerating wall), without relying a specific particle physics model....
We re-examine the production of gravitational waves by bubble collisions during a first-order phase transition. The spectrum radiation is determined numerical simulations using 'envelope approximation'. find that rises as f3.0 for small frequencies and decreases f−1.0 high frequencies. Thus, fall-off at significantly slower than previously stated in literature. This result has direct impact on detection prospects gravity originating from strong electroweak transition space-based...
It is well known that the electroweak phase transition (EWPhT) in extensions of Standard Model with one real scalar singlet can be first-order for realistic values Higgs mass. We revisit this scenario most general renormalizable potential systematically identifying all regions parameter space develop, due to tree-level dynamics, a barrier at critical temperature strong enough avoid sphaleron wash-out baryon asymmetry. Such EWPhTs allow simple mean-field approximation and an analytic...
In this paper we discuss some general aspects of the gravitational wave background arising from postinflationary short-lasting cosmological events such as phase transitions. We concentrate on physics which determines shape and peak frequency spectrum. then apply our findings to case bubble collisions during a first order transition compare different results in recent literature.
We investigate the potential for observing gravitational waves from cosmological phase transitions with LISA in light of recent theoretical and experimental developments. Our analysis is based on current state-of-the-art simulations sound cosmic fluid after transition completes. discuss various sources radiation, underlying parameters describing a variety viable particle physics models this context, clarifying common misconceptions that appear literature identifying open questions requiring...
Abstract Gravitational waves from a first-order cosmological phase transition, at temperatures the MeV-scale, would arguably be most exciting explanation of common red spectrum reported by NANOGrav collaboration, not least because this direct evidence physics beyond standard model. Here we perform detailed analysis whether such an interpretation is consistent with constraints on released energy deriving big bang nucleosynthesis and cosmic microwave background. We find that transition in...
We discuss some cosmological implications of extensions the standard model with hidden-sector scalars coupled to Higgs boson. put special emphasis on conformal case, in which electroweak symmetry is broken radiatively a mass above experimental limit. Our refined analysis phase transition this kind models strengthens prediction strongly first-order as required by baryogenesis. further study gravitational wave production and possibility low-scale inflation well viable dark matter candidate.
We show that simple Two Higgs Doublet models still provide a viable explanation for the matter-antimatter asymmetry of Universe via electroweak baryogenesis, even after taking into account recent order-of-magnitude improvement on electron-EDM experimental bound by ACME Collaboration. Moreover we that, in region parameter space where baryogenesis is possible, gravitational wave spectrum generated at end phase transition within sensitivity reach future space-based interferometer LISA.
We address electroweak baryogenesis in the context of composite Higgs models, pointing out that modifications to and top quark sectors can play an important rôle generating baryon asymmetry. Our main observation is models include a light, gauge singlet scalar spectrum [as model based on symmetry breaking pattern SO(6) → SO(5)], provide all necessary ingredients for viable baryogenesis. In particular, leads strongly first-order phase transition introduces new sources CP violation...
We review the mechanism of electroweak baryogenesis. Our focus is on derivation quantum transport equations from first principles within Schwinger-Keldysh formalism. emphasize importance semiclassical force approach, which provides reliable predictions in most models. In light recent electric dipole moment measurements and given results new physics searches collider experiments, status baryogenesis discussed a variety
The Higgs effective potential in the Standard Model (SM), calculated perturbatively, generically suffers from infrared (IR) divergences when (field-dependent) tree-level mass of Goldstone bosons goes to zero. Such can affect both and its first derivative become worse with increasing loop order. In this paper we show that these IR are spurious, perform a simple resummation all IR-problematic terms known (up three loops) explain how extend cure such any method is general applicability would...
We perform simulations in a simple model that aims to mimic the hydrodynamic evolution of relativistic fluid during cosmological first-order phase transitions. The observable we are concerned with is hereby spectrum gravitational radiation produced by colliding shells. present parameterizations our results as functions wall velocity, duration transition and latent heat. also improve on previous envelope approximation compare simulations.
By means of a relativistic microscopic approach we calculate the expansion velocity bubbles generated during first-order electroweak phase transition. In particular, use gradient Kadanoff-Baym equations to set up fluid system. This turns out be equivalent one found in semi-classical non-relativistic limit. Finally, by including hydrodynamic deflagration effects and solving Higgs motion fluid, determine thickness bubble walls. Our findings are compared with phenomenological models wall...
We provide an easy method to obtain the kinetic energy fraction in gravitational waves, generated during a cosmological first-order phase transition, as function of only wall velocity and quantities that can be determined from particle physics model at nucleation temperature. This generalizes recent work achieved this goal for detonations. Here we present corresponding results deflagrations hybrids. Unlike detonations, sound speed symmetric also enters analysis. perform detailed comparison...
Abstract We revisit the computation of bubble wall friction during a cosmological first-order phase transition, using an extended fluid Ansatz to solve linearized Boltzmann equation. A singularity is found in fluctuations background species as approaches speed sound. Using hydrodynamics, we argue that discontinuity across sound expected on general grounds, which manifests itself solution system. discuss this result comparison with alternative proposed recently, find regular behaviour for all...
We introduce a model for matters-genesis in which both the baryonic and dark matter asymmetries originate from first-order phase transition sector with an $SU(3)\times SU(2)\times U(1)$ gauge group minimal content. In simplest scenario, we predict that is antineutron mass either $m_{\bar{n}} = 1.36$ GeV or 1.63$ GeV. Alternatively, may be comprised of equal numbers antiprotons pions. This model, highly discoverable through direct detection photon search experiments. The strong self...
Abstract First-order cosmological phase transitions in the early Universe source sound waves and, subsequently, a background of stochastic gravitational waves. Currently, predictions these rely heavily on simulations Higgs field coupled to plasma Universe, former providing latent heat transition. Numerically, this is rather demanding task since several length scales enter dynamics. From smallest largest, are thickness interface separating different phases, shell waves, and average bubble...
During a strongly first-order phase transition gravitational waves are produced by bubble collisions and turbulent plasma motion. We analyze the relevant characteristics of electroweak in nMSSM to determine generated wave signal. Additionally, we comment on correlations between production baryogenesis. conclude that relic density this model is generically too small be detected near future LISA experiment. also consider case 'standard model' with dimension-six Higgs potential, which leads...
We study radion stabilization in the compact Randall-Sundrum model by introducing a bulk scalar field, as Goldberger and Wise mechanism, but (partially) taking into account backreactions from field on metric. Our generalization reconciles potential found with mass obtained so-called superpotential method where backreaction is fully considered. Moreover we holographic phase transition its gravitational wave signals this model. The improved control over opens up large region parameter space...
Nearly conformal dynamics at the TeV scale as motivated by hierarchy problem can be characterized a stage of significant supercooling electroweak epoch. This has important cosmological consequences. In particular, common assumption about history universe is that reheating temperature high, least high enough to assume TeV-mass particles were once in thermal equilibrium. However, we discuss this paper, not well justified some models strong scale. We then need reexamine how achieve baryogenesis...
In principle, observables as for example the sphaleron rate or tunneling in a first-order phase transition are gauge-independent. However, practice gauge dependence is introduced explicit perturbative calculations due to breakdown of gradient expansion effective action symmetric phase. We exemplify situation using potential Abelian Higgs model general renormalizable gauge. Still, we find that quantitative on choice small gauges consistent with expansion.