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On the Constant-Roll Tachyon Inflation with Large and Small η_{H}

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Duality in Canonical Inflation

## 3. Duality in Tachyon Inflation

#### 3.1. The Scalar Perturbation

#### 3.2. The Tensor Perturbation

#### 3.3. The Duality and Observation

## 4. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## References

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**Figure 1.**(

**Left panel**) shows the marginalized 68%, and 95% confidence level contours for ${n}_{s}$ and r from Planck 2018 and the observational constraints on the constant-roll inflationary models whereas the (

**Right panel**) shows observational constraints on ${\eta}_{H}$ and N for 68% (red) and 95% (green) C.L.s, respectively for small ${\eta}_{H}$.

**Figure 2.**(

**Left panel**) shows the marginalized 68%, and 95% confidence level contours for ${n}_{s}$ and r from Planck 2018 and the observational constraints on the constant-roll inflationary models whereas the (

**Right panel**) shows observational constraints on ${\eta}_{H}$ and N for $68\%$(red) and $95\%$ (green) C.L.s, respectively for large ${\eta}_{H}$.

**Figure 3.**The difference of ${n}_{s}$ and r between the tachyon inflation models with large $\eta $ and small $\eta $. The black line is the results from the tachyon inflation with small $\eta $, and the green dots are the results from the large $\eta $.

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**MDPI and ACS Style**

Fei, Q.; Ahmed, W.; Wang, Z.-L.
On the Constant-Roll Tachyon Inflation with Large and Small *η*_{H}. *Symmetry* **2022**, *14*, 2670.
https://doi.org/10.3390/sym14122670

**AMA Style**

Fei Q, Ahmed W, Wang Z-L.
On the Constant-Roll Tachyon Inflation with Large and Small *η*_{H}. *Symmetry*. 2022; 14(12):2670.
https://doi.org/10.3390/sym14122670

**Chicago/Turabian Style**

Fei, Qin, Waqas Ahmed, and Zhen-Lai Wang.
2022. "On the Constant-Roll Tachyon Inflation with Large and Small *η*_{H}" *Symmetry* 14, no. 12: 2670.
https://doi.org/10.3390/sym14122670