# Scalar–Tensor–Vector Modified Gravity in Light of the Planck 2018 Data

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## Abstract

**:**

## 1. Introduction

`CMBFAST`[4]. Unfortunately, such software packages cannot be easily adapted for use with a variable-G theory of gravitation, such as the Scalar–Tensor–Vector–Gravity (STVG [5]) theory, also known as MOdified Gravity (MOG).

## 2. The MOG Theory

## 3. Modeling the Cosmic Microwave Background (CMB)

#### 3.1. Semi-Analytical Estimation of CMB Anisotropies

#### 3.2. The MOG CMB Spectrum

## 4. Conclusions

## Acknowledgments

## Conflicts of Interest

## Notes

1 | |

2 | For important explanations see https://wiki.cosmos.esa.int/planck-legacy-archive/index.php/CMB_spectrum_%26_Likelihood_Code (accessed on 15 September 2021). |

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**Figure 1.**Mukhanov’s approximation of the angular power spectrum in light of Planck 2018 data. Thick blue line: Mukhanov’s approximation as a sum of an oscillatory part (thin dotted red line) and a nonoscillatory part (dashed green line). Planck 2018 data are shown in light blue with vertical error bars. Top row: standard cosmology, with nominal parameters (left) and least squares fitted values for ${\Omega}_{b}$ and ${n}_{s}$ (right). Bottom row: The MOG theory, with ${\Omega}_{b}$, $\alpha $ and ${n}_{s}$ fitted (left) and with the same 3-parameter fit but setting ${H}_{0}=73$ km/s/Mpc fitted (right).

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Moffat, J.W.; Toth, V.
Scalar–Tensor–Vector Modified Gravity in Light of the Planck 2018 Data. *Universe* **2021**, *7*, 358.
https://doi.org/10.3390/universe7100358

**AMA Style**

Moffat JW, Toth V.
Scalar–Tensor–Vector Modified Gravity in Light of the Planck 2018 Data. *Universe*. 2021; 7(10):358.
https://doi.org/10.3390/universe7100358

**Chicago/Turabian Style**

Moffat, John W., and Viktor Toth.
2021. "Scalar–Tensor–Vector Modified Gravity in Light of the Planck 2018 Data" *Universe* 7, no. 10: 358.
https://doi.org/10.3390/universe7100358