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Gravitoelectromagnetism: L’art Pour L’art—Or a Subject for the Classroom^{ †}

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## Abstract

**:**

## 1. Introduction

## 2. Shortcomings of the Classical Theory of Gravity

## 3. What Distinguishes Gravitation and Electromagnetism

## 4. Mechanical Stress and Energy Density

#### 4.1. Mechanical Stress within the Electric Field

#### 4.2. Mechanical Stress within the Gravitoelectric Field

## 5. Energy Flow

#### 5.1. Energy Exchange with the Gravitational Field of the Earth

#### 5.2. A Closed Energy Circuit

## 6. Conclusions

**g**but also the gravitomagnetic field strength

**b**, as well as the analogous Maxwell equations. One should not do this in the introductory mechanics lecture, because at that time the students are not yet familiar with Maxwell’s theory. We, therefore, suggest devoting about two lessons of the lecture to electromagnetism. Not only does it give the students a new view on gravity, it is also a good exercise for dealing with Maxwell’s theory.

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## References

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**Figure 1.**(

**a**) The electric field pulls outward on the sphere; (

**b**) with the charge kept constant, new field has been created. For this, energy had to be supplied to the system; (

**c**) spring model: the mechanical stresses were discretized.

**Figure 2.**(

**a**) The gravitational field pushes on the sphere; (

**b**) with the mass kept constant, new field has been created. For this, energy had to be removed from the system; (

**c**) spring model: the mechanical stresses were discretized.

**Figure 3.**The rod is moved upwards. In the process, energy flows within the rod from top to bottom. This energy gradually leaves the rod sideways.

**Figure 4.**In the left part of the rope, the energy flows upward, in the right part downward. In the process, its current strength increases upwards in the left part and decreases downwards in the right part. The circuit is closed by the gravitational field in which the energy flows from the right to the left part of the rope.

**Figure 5.**Energy flow corresponding to Figure 4, schematically.

**Figure 6.**Horizontal section through the arrangement of Figure 4. The field lines of the $g$ field point into the drawing plane. From the right to the left section of the rope, the energy flows through the gravitational field.

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**MDPI and ACS Style**

Herrmann, F.; Pohlig, M.
Gravitoelectromagnetism: L’art Pour L’art—Or a Subject for the Classroom. *Phys. Sci. Forum* **2021**, *2*, 56.
https://doi.org/10.3390/ECU2021-09282

**AMA Style**

Herrmann F, Pohlig M.
Gravitoelectromagnetism: L’art Pour L’art—Or a Subject for the Classroom. *Physical Sciences Forum*. 2021; 2(1):56.
https://doi.org/10.3390/ECU2021-09282

**Chicago/Turabian Style**

Herrmann, Friedrich, and Michael Pohlig.
2021. "Gravitoelectromagnetism: L’art Pour L’art—Or a Subject for the Classroom" *Physical Sciences Forum* 2, no. 1: 56.
https://doi.org/10.3390/ECU2021-09282