# A Review of Searches for Evidence of Tachyons

## Abstract

**:**

## 1. Introduction

## 2. Tachyons as New Particles

## 3. Neutrinos as Tachyons

## 4. Hints from IceCube Data

## 5. Energetically Forbidden $\mathit{\beta}-$Decay

## 6. The Cosmic Ray Spectrum

## 7. A n-p Decay Chain?

## 8. SN 1987A and Its Neutrinos

## 9. The $\mathbf{3}+\mathbf{3}$ Neutrino Model

## 10. The $\mathbf{3}+\mathbf{3}+\mathit{L}\mathit{C}\mathit{R}$ Model

## 11. Evidence for the $\mathbf{3}+\mathbf{3}$ Model

#### 11.1. The ${m}^{2}>0$ Masses in the $3+3$ Model

#### 11.2. The ${m}^{2}<0$ Mass in the $3+3$ Model

## 12. Neutrino Mass Experiments

## 13. The KATRIN Experiment

## 14. $\mathbf{3}+\mathbf{3}$ Model and Cosmology

## 15. Summary and Future Tests

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**Plot of missing mass, that is the mass of X for the reaction ${K}^{-}+p\to {\mathsf{\Lambda}}^{0}+X$.

**Figure 2.**Plot of ${E}^{3}J\equiv {E}^{3}dF/dE$ for the cosmic ray spectrum using data from the four indicated experiments showing the locations of the two knees, the ankle, and the GZK cut-off.

**Figure 3.**Plot of $1/{E}^{2}$ versus neutrino arrival time t for 25 neutrinos from SN 1987A providing evidence for two masses, based on the clustering of neutrino events near two straight lines.

**Figure 4.**

**The 3 + 3 model.**${m}^{2}$ values in eV${}^{2}$ for the three active–sterile doublets in the model and their splittings, $d{m}^{2}$. The choice of ${m}_{3}$ was made so that the three doublets have a common fractional splitting, $d{m}^{2}/{m}^{2}.$ The plot is not to scale.

**Figure 5.**

**The 3 + 3 + LCR model.**Three active–sterile pairs having the indicated ${m}^{2}$ values under the assumptions of LCR symmetry and the $d{m}^{2}$ values observed in neutrino oscillation data (including $d{m}_{sbl}^{2}).$ It is further assumed that oscillations are predominantly between states having the same $\left|m\right|.$ Whether the active or sterile states have ${m}^{2}>0$ is unspecified. The plot is not to scale.

**Figure 6.**Predicted percentage deviations from the single mass $m=0$ integrated spectrum for the $3+3$ model, for three choices of the contribution from the ${m}_{1}=4$ eV mass. The choice of $94\%$ results in the smallest departure from the single mass spectrum, namely <0.8% at all energies.

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Ehrlich, R.
A Review of Searches for Evidence of Tachyons. *Symmetry* **2022**, *14*, 1198.
https://doi.org/10.3390/sym14061198

**AMA Style**

Ehrlich R.
A Review of Searches for Evidence of Tachyons. *Symmetry*. 2022; 14(6):1198.
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**Chicago/Turabian Style**

Ehrlich, Robert.
2022. "A Review of Searches for Evidence of Tachyons" *Symmetry* 14, no. 6: 1198.
https://doi.org/10.3390/sym14061198