# Nonsingular Black Holes in ƒ (R) Theories

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## Abstract

**:**

## 1. Introduction

## 2. Field Equations and Matter Source

## 3. Structure Equations

## 4. Wormhole geometry

**Figure 1.**Representation of the radial function $r\left(x\right)$ in units of the scale ${r}_{c}$ for the cases $\alpha =1/10,1/2,4/5$ (colors blue, green, and orange, respectively). The dashed lines represent the function $|x|$, corresponding to the General Relativity (GR) case, which is quickly recovered for $x>2$. As can be seen, the dependence on α is very weak.

## 5. Geodesics

**Figure 2.**Representation of outgoing (green) and ingoing (red) null radial geodesics with $E=1$ and $\alpha =4/5$. Similar results are found for any other value $0<\alpha <1$.

## 6. Summary and Conclusions

## Acknowledgments

## Author Contributions

## Conflicts of Interest

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Olmo, G.J.; Rubiera-Garcia, D.
Nonsingular Black Holes in ƒ (*R*) Theories. *Universe* **2015**, *1*, 173-185.
https://doi.org/10.3390/universe1020173

**AMA Style**

Olmo GJ, Rubiera-Garcia D.
Nonsingular Black Holes in ƒ (*R*) Theories. *Universe*. 2015; 1(2):173-185.
https://doi.org/10.3390/universe1020173

**Chicago/Turabian Style**

Olmo, Gonzalo J., and Diego Rubiera-Garcia.
2015. "Nonsingular Black Holes in ƒ (*R*) Theories" *Universe* 1, no. 2: 173-185.
https://doi.org/10.3390/universe1020173