Einstein field equations

In summary, the Einstein field equations (EFE) are a set of ten interrelated differential equations formulated by Albert Einstein in 1915 as part of his General Theory of Relativity. They describe how matter and energy in the universe influence the curvature of spacetime, which in turn affects the motion of objects. The equations relate the geometry of spacetime, represented by the Einstein tensor, to the energy and momentum content of that spacetime, represented by the stress-energy tensor. The EFE are fundamental to understanding gravitational phenomena and have significant implications in cosmology, astrophysics, and the study of black holes.
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I am still in high school but can someone explain these to me in short detail . I know what tensors are and i can solve Basic Inertia tensor matrices to find torque without official education on it . What do i need to do in order to learn these equations and understand them exactly.(Time is not a concern for me right now ) .Any video suggestions or books?or anything will be helpful .Please also explain what the symbols mean .Thanks
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Start with special relativity. All treatments of general relativity will assume you understand special relativity. Then make sure you know calculus, including differential equations and partial differentiation. And linear algebra generally.

Taylor and Wheeler's Spacetime Physics is free to download from Taylor's website, and should be in reach for a sufficiently motivated high school student.

A former mentor here, Ben Crowell, wrote a book called Relativity for Poets, which is downloadable via www.lightandmatter.com. It's a non-mathematical treatment, and about as good as you can get without maths.

Regarding the field equations, roughly speaking ##G_{ab}## describes the curvature of spacetime. ##\Lambda g_{ab}## describes the contribution of the cosmological constant, and is sometimes rolled into the term on the right. ##T_{ab}## is the stress-energy tensor, which describes all the energy (including mass) terms that are sources of gravity.
 
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PhysicsEnjoyer31415 said:
What do i need to do in order to learn these equations and understand them exactly.(Time is not a concern for me right now ) .Any video suggestions or books?or anything will be helpful .Please also explain what the symbols mean .Thanks

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It's unlikely that a particular video or book suggestion will happen to hit the "sweet spot" for you. This video might be too elementary. It builds up to Einstein's equation with interesting historical commentary. It also discusses the meaning of the symbols in the equation, but not in much depth.

Einstein's equation in the video does not contain the term ##\Lambda g_{\mu \nu}##. The ##G_{\mu \nu}## in your equation represents all of the left-hand side of Einstein's equation in the video.
 
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Thank you people👍
 
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FAQ: Einstein field equations

What are the Einstein field equations?

The Einstein field equations (EFE) are a set of ten interrelated differential equations in the theory of general relativity, formulated by Albert Einstein. They describe how matter and energy in the universe influence the curvature of spacetime, which we perceive as gravity. The equations relate the geometry of spacetime to the distribution of matter within it.

What do the Einstein field equations represent?

The EFE represent the fundamental relationship between the geometry of spacetime and the energy-momentum content of that spacetime. In simple terms, they express how mass and energy tell spacetime how to curve, and conversely, how curved spacetime affects the motion of objects within it.

What is the mathematical form of the Einstein field equations?

The mathematical form of the Einstein field equations can be expressed as: Gμν = 8πGTμν, where Gμν is the Einstein tensor that describes the curvature of spacetime, Tμν is the stress-energy tensor that describes the distribution of matter and energy, G is the gravitational constant, and c is the speed of light. This equation encapsulates the core idea of general relativity.

How are the Einstein field equations solved?

Solving the Einstein field equations typically involves finding a metric that satisfies the equations under specific conditions or symmetries. This can be a complex task, often requiring numerical methods or approximations, especially in scenarios involving strong gravitational fields or dynamic systems. Common solutions include the Schwarzschild solution for a non-rotating black hole and the Friedmann-Lemaître-Robertson-Walker metric for cosmological models.

What are some applications of the Einstein field equations?

The Einstein field equations have numerous applications in astrophysics and cosmology, including the study of black holes, gravitational waves, the expansion of the universe, and the behavior of neutron stars. They also play a crucial role in understanding gravitational phenomena and the overall dynamics of the cosmos.

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