Analog of Gauss' law in gravity

In summary, Gauss's law in electrostatics states that the electric flux through a closed surface is equal to the enclosed charge divided by the permittivity of free space. This concept can also be applied to gravity, where the gravitational flux through a closed surface is equal to the enclosed mass multiplied by a constant. However, in this case, the gravitational force is always attractive and the field is represented by the variable ##\vec{g}##. While not as well-known as Gauss's law for electrostatics, it can be easily understood by physicists with a brief explanation.
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LagrangeEuler
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Gauss law in case of sphere which has charge ##q## is ##\oint \vec{E}\cdot d\vec{S}=\frac{q}{\epsilon_0}##

Is there some anologone for case of sphere with mass ##m## such that
##\oint \vec{G}\cdot d\vec{S}=4\pi \gamma m ## and what is ##\vec{G}## in that case?
 
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Yes - it is Gauss' law for gravitation. Note that it differs from Gauss' law in electrostatics by the presence of a minus sign on the right:
[tex] \oint_{\partial V} \vec{g} \cdot d\vec{S} = -4\pi Gm [/tex]
This is because gravitation is strictly attractive, while the electrostatic force can be either attractive or repulsive. The field ## \vec{g} ## is the gravitational field, defined completely analogously to the electric field whereby the force experienced by a particle of mass ## \mu ## in the field is ## \vec{F}_{g} = \mu \vec{g} ##.
 
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Likes Dr. Courtney
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https://en.wikipedia.org/wiki/Gauss's_law_for_gravity

Gauss's law for gravity is not nearly as well known. I recall some years ago my wife gave a talk in a physics department and referred to it.

There were plenty of physicists in the room who were not familiar with the idea, but everyone quickly grasped it with a 30 second explanation.
 

What is Gauss' law in gravity?

Gauss' law in gravity is a fundamental law of physics that relates the distribution of mass or energy to the gravitational field it produces. It states that the gravitational flux through any closed surface is equal to the enclosed mass or energy divided by the gravitational constant.

Why is Gauss' law important in understanding gravity?

Gauss' law is important because it allows us to calculate the strength and direction of the gravitational field produced by a given distribution of mass or energy. This is crucial for understanding how objects move and interact under the influence of gravity.

What is the analog of Gauss' law in gravity?

The analog of Gauss' law in gravity is a similar law that applies to gravitational fields in the framework of general relativity. It states that the flux of the curvature of spacetime through any closed surface is equal to the enclosed mass or energy divided by the speed of light squared.

How does the analog of Gauss' law in gravity differ from the original Gauss' law?

The main difference is that the analog of Gauss' law takes into account the curvature of spacetime, whereas the original Gauss' law only considers the flat space geometry. Additionally, the analog of Gauss' law is derived from the principles of general relativity, while the original Gauss' law is based on Newton's law of gravitation.

What are some applications of the analog of Gauss' law in gravity?

The analog of Gauss' law is used in many areas of astrophysics and cosmology, such as modeling the gravitational fields of galaxies and clusters of galaxies. It is also important in understanding the properties of black holes and the overall structure and evolution of the universe.

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