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Relativity/Description of the Universe with only the Earth and then nothing.

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Question
Hello,
I have a curiosity and maybe with your help I can remove it.

The imagination has no boundaries, and then I would imagine that the entire Universe
there is only the earth without stars, galaxies, nothing.
Which description of this situation you could give?
The gravity on Earth would be the same?
And if you throw a light signal from the Earth, as would proceed?
Follow a geodesic or what?
The apple falling from the tree always follow the same path?
My weight always the same? So things like that.

Answer
Nello, sorry to be late with an answer.  I didn't get the e-mail.

All of your questions have the answer YES, almost.  The sun contributes a small amount to Earth's gravity, but not much. Of course, it would get pretty cold here without the sun, but the gravity is mostly due to the Earth. A light beam would be bent by the sun, but it would still propagate without it fine.

Ben

Relativity

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Uncle Ben

Expertise

I can answer questions regarding Einstein's Theory of Relativity, particularly in Special Relativity. I will not answer homework questions or mathematical problems that require special symbols.

Experience

I have taught physics at the college level, undergraduate and graduate, for many years including Special Relativity. I have taught at Johns Hopkins, Case-Western, and MIT. I have also served as a staff member of the Commission on College Physics, which was supported by the National Science Foundation to recommend improvements in the curriculum of college physics departments in the US. I am also the author of a textbook titled Vector Calculus, which was used at MIT in the teaching of electromagnetic theory and relativity. My research interests were mainly in solid state physics, especially the properties of metals at low temperatures. I am listed in the publication known as American Men of Science.

Publications
I have dozens of papers published in the Physical Review and in the American Journal of Physics.

Education/Credentials
I hold a Ph.D. degree in physics from the Johns Hopkins University.

Past/Present Clients
Johns Hopkins University, Case-Western Reserve University, Massachusetts Institute of Technology, Empire State College, Georgetown University, Commission on College Physics, and UNESCO.

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