# Gravitational Interaction in a Null String Gas and Its Possible Consequences

## Abstract

**:**

## 1. Introduction

- For a test null string, there is always only a narrow region (the interaction zone) in which the test null string may interact with the null string (source), which indicates the possibility of a grained structure of space filled with null string gas;
- For each test null string that falls into the interaction zone, there is abnormal segments of the trajectory, where, for an extremely short period of time, the test null string is either pushed to infinity with acceleration or gravitated from infinity with acceleration. It confirms, although indirectly, the hypothesis of the possible string nature of the universe inflation mechanism;
- It is shown that an existence of the state (phase) of null string gas in which closed strings are located in parallel planes (the polarization effect) and move towards the same direction with no change in their initial shape (i.e., they form a null string domain) is possible;
- An influence of the gravitational field of a null string domain may lead to stable in time oscillations of a test null string inside a limited region of space. These stable in time and limited in space regions may be considered as particles localized in space with an effective nonzero rest mass.

## 2. Gravitational Field of a Source Null String

## 3. The Motion of a Test Null String in a Gravitational Field (4)

## 4. The Motion of a Test Null String in a Gravitational Field (8)

## 5. Graphs of the Motion of the Test Null String in a Variable Corresponding to the Direction of Motion of the Source Null String

## 6. Graphs of the Motion of the Test Null String in a Variable That Is Orthogonal to the Direction of Motion of the Source Null String

## 7. Gravitational Null Strings Interaction

## 8. Discussion

## Funding

## Conflicts of Interest

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**Figure 1.**The figure shows a graph of the change in the position of the test null string on the z axis in the case when the source null string moves in the negative direction of the z axis without change of the radius.

**Figure 2.**The figure shows a graph of the change of the position of the test null string on the z axis in the case when the source null string moves in the positive direction of the z axis without change of the radius.

**Figure 3.**The figure shows graphs of changes of the radius of a test null string in the case when the source null string respectively radially increases (

**a**) and radially decreases (

**b**) its size (radius), being on the surface $z={z}_{0}$.

**Figure 4.**The figure (

**a**,

**b**) shows the graphs of the change of the radius of the test null string in the case when the source null string moves along the z axis without change of the radius.

**Figure 5.**The figure (

**a**,

**b**) shows the graphs of the position of the test null string on the z axis in the case when the source null string radially decreases or increases its size (radius), being on the surface $z={z}_{0}$.

**Figure 6.**The figure shows qualitatively the trajectories of motion of two gravitationally interacting null strings, the meeting surface for which is orthogonal to the z axis ($z={z}_{o}$).

**Figure 7.**The figure shows qualitatively the trajectories of motion of two gravitationally interacting null strings, the meeting surface for which is orthogonal to the $\rho $ axis ($\rho ={R}_{o}$).

**Figure 8.**The figure shows qualitatively the trajectories of motion of two gravitationally interacting null strings, the meeting surfaces for which alternates (surfaces $z={z}_{o}$ and $\rho ={R}_{o}$).

**Figure 9.**The figure shows the admissible (

**a**) and not admissible (

**b**) spatial arrangement of two pairs of gravitationally interacting null strings.

**Figure 10.**The figure shows qualitatively the trajectories of motion of three gravitationally interacting null strings, the meeting surface for which is orthogonal to the $\rho $ axis ($\rho ={R}_{o}$).

**Figure 11.**In the figure (

**a**,

**b**), two possibilities of combination of gravitationally interacting null strings into a spherically symmetric domain are schematically presented.

Position on the z Axis | ||
---|---|---|

Point | Test Null String | Source Null String |

${A}_{\parallel 1}$ | $z=0.1$ | $z=1$ |

${B}_{\parallel 1}$ | $z=-0.1$ | $z=0.1$ |

${C}_{\parallel 1}$ | $z=0$ | $z=0$ |

${D}_{\parallel 1}$ | $z=0.1$ | $z=-0.1$ |

${E}_{\parallel 1}$ | $z=-0.1$ | $z=-1$ |

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**MDPI and ACS Style**

Lelyakov, A.
Gravitational Interaction in a Null String Gas and Its Possible Consequences. *Universe* **2020**, *6*, 142.
https://doi.org/10.3390/universe6090142

**AMA Style**

Lelyakov A.
Gravitational Interaction in a Null String Gas and Its Possible Consequences. *Universe*. 2020; 6(9):142.
https://doi.org/10.3390/universe6090142

**Chicago/Turabian Style**

Lelyakov, Alexander.
2020. "Gravitational Interaction in a Null String Gas and Its Possible Consequences" *Universe* 6, no. 9: 142.
https://doi.org/10.3390/universe6090142