Spacetime, curvature, orbit, matter and reactions

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The forum discussion centers on the analogy used in the BBC film "Einstein and Eddington" to explain spacetime, where a tablecloth represents space, a loaf of bread symbolizes the sun, and a piece of fruit illustrates a planet's orbit. Participants critique the analogy, noting its limitations, particularly the absence of a time dimension crucial for General Relativity. The conversation also touches on gravitational lensing and optical effects, emphasizing that while shadows are not caused by spatial curvature, optical distortions can occur. Overall, the discussion highlights the complexities of visualizing spacetime and gravitational interactions.

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Elliot.exe
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In the BBC film Einstein and Eddington, Eddington describes the theory of spacetime using a table cloth (space), a loaf of bread (sun) and a piece of fruit (a planet).

The Bread is placed in the middle of the table cloth, this forms curves in the cloth. He then takes a piece of fruit and throws it in. The fruit oribits the bread along the curves. This shows spacetime.

This provoked and idea in my head, The sun is a source of light, In the curves of the cloth there are shadows caused by the sun. The curves of space might have light from the sun causing a "shadow" of light particles or matter in the same way there was a shadow in the cloth. I also think this might cause a reaction as a planet orbits. the idea is rough but in theory it could work.

Or is it all just, like Thunderbirds just string theory

Elliot.exe
 
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Well, I wouldn't take the table cloth analogy too seriously (it has big flaws) but you can get gravitational lensing, so I would think you could get other optical effects like shadows.
 
Elliot.exe said:
In the BBC film Einstein and Eddington, Eddington describes the theory of spacetime using a table cloth (space), a loaf of bread (sun) and a piece of fruit (a planet).

The Bread is placed in the middle of the table cloth, this forms curves in the cloth. He then takes a piece of fruit and throws it in. The fruit oribits the bread along the curves. This shows spacetime.
No this is not spacetime. This is just space (2 dimensions of it). There is no time dimension in this analogy which is crucial for the gravity model of General Relativity. Follow the links in this post, for better visualizations:
https://www.physicsforums.com/showthread.php?p=2046692

Elliot.exe said:
This provoked and idea in my head, The sun is a source of light, In the curves of the cloth there are shadows caused by the sun. The curves of space might have light from the sun causing a "shadow" of light particles or matter in the same way there was a shadow in the cloth.
You are completely misunderstanding the analogy here. The cloth itself represents the space in which light is propagating. So in this analogy the light from the bread (sun) would propagate only within the cloth, not outside of it. There are no shadows caused by spatial curvature around the sun, but optical distortions are possible as DaleSpam said.
 
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