BEGIN:VCALENDAR VERSION:2.0 PRODID:-//linuxsoftware.nz//NONSGML Joyous v1.4//EN BEGIN:VEVENT SUMMARY:Probing unification scenarios with Big Bang Nucleosynthesis DTSTART:20251104T150000Z DTEND:20251104T170000Z DTSTAMP:20260804T190936Z UID:726ffda2-4550-4d46-bd2b-f8c9af69e989 SEQUENCE:4 CREATED:20251027T095921Z DESCRIPTION:Big Bang Nucleosynthesis (BBN) is an observational cornerstone of the Hot Big Bang model and a sensitive probe of physics beyond it. Alt hough some analytic approximations can be made\, a fully consistent analys is must be done numerically\, starting with the classic code by Kawano and leading to the recently developed PRyMordial\, a publicly available Pytho n code.An example of physics beyond the standard model to which BBN is sen sitive are Grand Unified Theory (GUT) models. A self-consistent perturbati ve analysis of the effects of variations in nature’s fundamental constan ts\, unavoidable in a broad class of GUT models\, has recently been develo ped\, and describes the relevant variations with only three parameters: ( ∆α_EM)/α_EM \, R and S.The specific goal of this work is to implement this perturbative approach in the PRyMordial code and use the extended cod e to obtain constraints on the variations of the abovementioned fundamenta l constants using current observations.Two different viable scenarios were found\, and the three parameters were constrained independently for both cases. The variation of the gravitational coupling can be implemented by v arying either particle masses\, or Newton’s gravitational constant.With the variation of masses\, we obtained a 1σ interval of [-4.89×10^(-5)\,5 .22×10^(-5)] for (∆α_EM)/α_EM and a ratio S/R=2.53±0.06 correlating with the observational values of Helium-4 and Deuterium abundances.For the variation of G_N\, we obtained one (R\,S) point (-1.52\,-6.06) that works best for any (∆α_EM)/α_EM \, constraining each of the three in a 1σ interval: [-2.00×10^(-5)\,2.33×10^(-5) ] for ∆(∆α_EM)/α_EM \, [-15 .7\,16.2] for R\, and [-127.3\,135.4] for S. LAST-MODIFIED:20251027T115418Z LOCATION:Sala P3\, Piso 1\, Pavilhão de Matemática\, Campus Alameda/Onli ne URL:http://df.vps.tecnico.ulisboa.pt/pt/eventos/probing-unification-scenar ios-with-big-bang-nucleosynthesis/ X-ALT-DESC;FMTTYPE=text/html:

Big Bang Nucleosynt hesis (BBN) is an observational cornerstone of the Hot Big Bang model and a sensitive probe of physics beyond it. Although some analytic approximati ons can be made\, a fully consistent analysis must be done numerically\, s tarting with the classic code by Kawano and leading to the recently develo ped PRyMordial\, a publicly available Python code.

An example of physics beyond the standard model to which B BN is sensitive are Grand Unified Theory (GUT) models. A self-consistent p erturbative analysis of the effects of variations in nature’s fundamenta l constants\, unavoidable in a broad class of GUT models\, has recently be en developed\, and describes the relevant variations with only three param eters: (∆α_EM)/α_EM \, R and S.

The specific goal of this work is to implement this perturbative approach in the PRyMordial code and use the extended code to obtain constraints on the variations of the abovementioned fundamental constants using current observations.

Two different viable scenarios were found\, and the three parameters were constrained independently for b oth cases. The variation of the gravitational coupling can be implemented by varying either particle masses\, or Newton’s gravitational constant.< br/>

With the variation of masses\, we o btained a 1σ interval of [-4.89×10^(-5)\,5.22×10^(-5)] for (∆α_EM)/ α_EM and a ratio S/R=2.53±0.06 correlating with the observational values of Helium-4 and Deuterium abundances.

For th e variation of G_N\, we obtained one (R\,S) point (-1.52\,-6.06) that work s best for any (∆α_EM)/α_EM \, constraining each of the three in a 1σ interval: [-2.00×10^(-5)\,2.33×10^(-5) ] for ∆(∆α_EM)/α_EM \, [-1 5.7\,16.2] for R\, and [-127.3\,135.4] for S.



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