2022/03/30 by P. P. Avelino, Avelino, P. P., D. Grüber +3 · 2 citations
Physics and Astronomy · #Astrophysics and Star Formation Studies #Cosmology and Gravitation Theories #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #General Relativity and Quantum Cosmology (gr-qc) #High Energy Physics - Phenomenology (hep-ph) #High Energy Physics - Theory (hep-th)
paper · pdf · doi:10.48550/arxiv.2203.16173
openalex publication_date 2022/03/30 · openalex created_date 2022/09/13 · openalex updated_date 2026/07/28
We derive an analytical approximation for the linear scaling evolution of the characteristic length L and the root-mean-squared velocity σv of standard frictionless domain wall networks in Friedmann-Lemaître-Robertson-Walker universes with a power law evolution of the scale factor a with the cosmic time t (a ∝ tλ). This approximation, obtained using a recently proposed parameter-free velocity-dependent one-scale model for domain walls, reproduces well the model predictions for λ close to unity, becoming exact in the λ→ 1- limit. We use this approximation, in combination with the exact results found for λ=0, to obtain a fit to the model predictions valid for λ∈ [0, 1[ with a maximum error of the order of 1 %. This fit is also in good agreement with the results of field theory numerical simulations, specially for λ∈ [0.9, 1[. Finally, we explicitly show that the phenomenological energy-loss parameter of the original velocity-dependent one-scale model for domain walls vanishes in the λ→ 1- limit and discuss the implications of this result.