arXiv subjects

Victor Muñoz-Vitelly

Publications and source records attributed to Victor Muñoz-Vitelly.

4 recordsLinked to original sources

arXiv2026

Non-standard cosmic strings with amazing profiles

It is an unnatural feature of the Standard Model that the difference between the baryon number $B$ and the lepton number $L$ is conserved, which implies an exact, global symmetry. We promote it to a naturally exact, local symmetry by coupling the difference $B-L$ to an Abelian gauge field. Gauge anomalies are cancelled by adding right-handed neutrinos $ν_{R}$. They are not sterile in this case, which forbids the Majorana term, but we arrange for a $ν_{R}$-mass by adding a Higgs-type 1-component complex scalar field. Thus we arrive at a well-motivated, modest extension of the Standard Model (SM). We investigate the field equations in the corresponding gauge-Higgs sector, involving both Higgs fields and the non-standard U(1) gauge field. This leads to a set of coupled, non-linear differential equations, which we solve numerically. We use cylindrical coordinates, thus focusing on the structures of cosmic strings. For a large variety of parameters, we identify the string profiles and energy densities. These profiles depend on the winding number of each of the Higgs fields. For our parameters, the characteristic string radii are below $10^{-3}~{\rm fm}$, and the string tension is not ruled out by observations of the Cosmic Microwave Background or gravitational waves. As an amazing peculiarity, we discover - for high winding numbers - ``overshooting'' and ``co-axial'' profile functions. In the latter case, the profile of the standard Higgs field changes its sign near the core of the cosmic string.

hep-ph↗

arXiv2025

Structure of cosmic strings for a gauged B-L symmetry and two Higgs fields

In the Standard Model, the difference between the baryon number $B$ and the lepton number $L$ is conserved, which represents a symmetry that is global and exact, and therefore unnatural. We turn it into a naturally exact, local symmetry by coupling the quantum number $B-L$ to an Abelian gauge field. Gauge anomalies are cancelled by adding right-handed neutrinos $ν_R$, which are not sterile in this case. Therefore the usual Majorana term is forbidden by gauge symmetry, but we arrange for a $ν_R$-mass by adding a Higgs-type 1-component complex scalar field. Thus we arrive at a modest, well-motivated extension of the Standard Model. In this framework, we investigate the field equations in the extended gauge-Higgs sector, involving both Higgs fields and the non-standard U(1) gauge field. They are given by a set of coupled, non-linear differential equations, which we solve numerically, focusing on the structures of cosmic strings. For a variety of parameters, we identify the string profiles and energy densities, assuming appropriate boundary conditions. In particular, these profiles depend on the winding number of each of the Higgs fields. As an amazing peculiarity, we discover -- for high winding numbers -- ``overshooting'' and ``co-axial'' solutions; in the latter case, the profile of the standard Higgs field changes its sign near the core of the cosmic string.

hep-ph↗

arXiv2022

Volume effects on the QCD critical end point from thermal fluctuations within the super statistics framework

We investigate the impact of the finite volume and the thermal fluctuations on the Critical End Point of the QCD phase diagram. To do so, we implement the super statistics framework with Gamma, $F$, and log-normal distributions and their relation with the Tsallis non-extensive thermodynamics. We compute an effective thermodynamic potential as a function of the inverse temperature fluctuations and explicit dependence on the system volume. To find an analytic expression for the effective potential, we expand the modified Boltzmann factor by using the equilibrium thermodynamic potential computed in the Linear Sigma Model coupled to quarks. We find that the pseudo-critical temperature of transition at vanishing baryon chemical potential is modified by the size of the system being about $7\%$ lower for small volumes. Additionally, the critical endpoint moves to higher densities and lower temperatures (about $12\%$ in both cases). Interestingly, the results are quantitatively the same when the parameter that models the out-of-equilibrium situation is modified, indicating that the chiral symmetry restoration is robust against the thermal fluctuations in this approximation.

hep-ph↗

arXiv2022

The structure of cosmic strings of a $U(1)$ gauge field for the conservation of $B-L$

We consider an extension of the Standard Model, where the difference between the baryon number $B$ and the lepton number $L$ is gauged with an Abelian gauge field, in order to explain the exact conservation of $B-L$. To avoid a gauge anomaly, we add a right-handed neutrino $ν_{\rm R}$ to each fermion generation. Here it is not sterile, so the usual Majorana term is excluded by gauge invariance. We provide a mass term for $ν_{\rm R}$ by adding a non-standard 1-component Higgs field, thus arriving at a consistent extension of the Standard Model, where the conservation of $B-L$ is natural, with a modest number of additional fields. We study the possible formation of cosmic strings by solving the coupled field equations of the two Higgs fields and the non-standard U(1) gauge field. Numerical methods provide the corresponding string profiles, depending on the Higgs winding numbers, such that the appropriate boundary conditions in the string center and far from it are fulfilled.

hep-ph↗