# Uniqueness of the Inflationary Higgs Scalar for Neutron Stars and Failure of Non-Inflationary Approximations

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## Abstract

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## 1. Introduction

## 2. Non-Inflationary Higgs Scalar-Tensor Gravity in the Einstein Frame and Static NSs Phenomenology

## 3. Concluding Remarks

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**$M-R$ graphs for the alternative non-inflationary Higgs model for the WFF1 EoS (purple curve), the APR EoS (blue curve), and the SLy EoS (red curve). The y-axis is expressed in $M/{M}_{\odot}$ units, with M denoting the Jordan frame ADM mass, and the x-axis is the circumferential radius.

**Figure 2.**The quantity $\xi {\varphi}^{2}$ (y-axis) in Geometrized units, versus the central densities in CGS units, for $\xi \sim 11.455\times {10}^{4}$, for the WFF1 (red curve), APR (blue curve) and Sly (green curve) EoSs. As it can be seen the constraint (12) is not satisfied.

Model | APR EoS | SLy EoS | WFF1 EoS |
---|---|---|---|

GR | ${M}_{max}=2.18739372\phantom{\rule{0.166667em}{0ex}}{M}_{\odot}$ | ${M}_{max}=2.04785291\phantom{\rule{0.166667em}{0ex}}{M}_{\odot}$ | ${M}_{max}=2.12603999\phantom{\rule{0.166667em}{0ex}}{M}_{\odot}$ |

Alternative Higgs$\mathbf{\xi}\sim {\mathbf{10}}^{\mathbf{4}}$ | ${M}_{max}=4.55374471\phantom{\rule{0.166667em}{0ex}}{M}_{\odot}$ | ${M}_{max}=4.41766131\phantom{\rule{0.166667em}{0ex}}{M}_{\odot}$ | ${M}_{max}=4.33460622\phantom{\rule{0.166667em}{0ex}}{M}_{\odot}$ |

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Oikonomou, V.K.
Uniqueness of the Inflationary Higgs Scalar for Neutron Stars and Failure of Non-Inflationary Approximations. *Symmetry* **2022**, *14*, 32.
https://doi.org/10.3390/sym14010032

**AMA Style**

Oikonomou VK.
Uniqueness of the Inflationary Higgs Scalar for Neutron Stars and Failure of Non-Inflationary Approximations. *Symmetry*. 2022; 14(1):32.
https://doi.org/10.3390/sym14010032

**Chicago/Turabian Style**

Oikonomou, Vasilis K.
2022. "Uniqueness of the Inflationary Higgs Scalar for Neutron Stars and Failure of Non-Inflationary Approximations" *Symmetry* 14, no. 1: 32.
https://doi.org/10.3390/sym14010032