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| bio | website | blog.vixra.org |
|---|---|---|
| location | England, United Kingdom | |
| age | 53 | |
| visits | member for | 2 years, 4 months |
| seen | 16 hours ago | |
| stats | profile views | 664 |
An independent physicist interest in general relativity, string theory and number theory.
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May 12 |
revised |
Distance away from earth to see it as a full disk added 654 characters in body |
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May 12 |
comment |
Distance away from earth to see it as a full disk Gemini-11 reached 1369km altitude in 1966 with 2 crew. Astronaut Richard Gordon did a space-walk at that altitude. Windows on these craft would reduce angle of view to much less than 120 degrees. Even a spacesuit helmet would reduce field of view during space-walks so not sure if Gordon could get the full disk effect. I will add info to answer. |
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May 12 |
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Distance away from earth to see it as a full disk I think Mike is right that field of view is about 120 degrees including peripheral vision. From 1000km outwards it will look disk-like. From moon it is 2 degrees across. Highest shuttle orbit was about 620km |
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May 12 |
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Distance away from earth to see it as a full disk The image is fixed now |
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May 12 |
revised |
Distance away from earth to see it as a full disk added 2 characters in body |
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May 12 |
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Distance away from earth to see it as a full disk Johannes, you are right thanks |
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May 11 |
revised |
Distance away from earth to see it as a full disk added 85 characters in body |
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May 11 |
answered | Distance away from earth to see it as a full disk |
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May 10 |
answered | Negative potential energy of gravity |
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May 7 |
comment |
Is there a closed form solution to the Esdale river problem? I think you should copy a description of the problem into the question otherwise the page at the link will eventually disappear and nobody will know what this question was about. |
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May 7 |
answered | Redshifting of Light and the expansion of the universe |
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May 7 |
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Is energy really conserved? If global hyperbolicity does not hold then lack of energy conservation would be the least of our worries. We would have serious problems solving the equations of motion at all. It is not an unreasonable assumption that it does hold in the real world so to say that energy is not conserved in this situation is a hypothetical feature of GR. Sean Carroll's arguments are completely different and I have refuted them and other objections in an article at vixra.org/abs/1305.0034 |
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May 7 |
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General relativity and the conservation of momentum @Ben, I have edited my answer to explain in detail why Misner, Thorne, and Wheeler are wrong. You could also have found this in general terms in my cited article. |
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May 7 |
revised |
General relativity and the conservation of momentum added 5292 characters in body |
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May 6 |
answered | General relativity and the conservation of momentum |
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May 6 |
answered | Energy Conservation Law validity |
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May 6 |
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photons in expanding space: how is energy conserved? This answer is correct. Even if you think there is something wrong with energy conservation the effect that radiation has on the expansion rate of the universe if determined by the Friedmann equations which are not controversial en.wikipedia.org/wiki/Friedmann_equations .Of course the effect is too small to be detectable which is perhaps why some people are confused. In any case energy conservation works perfectly well in this case see vixra.org/abs/1305.0034 |
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May 6 |
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curvature tensor component capable of doing work on $T_{\mu \nu}$ I don't want to reignite this discussion but I agree with Ron that energy conservation holds in cosmology and is correctly understood with the use of pseudotensors or more modern covariant methods. I have written an article vixra.org/abs/1305.0034 which retutes all the objections I have come across. |
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May 6 |
answered | Have red shifted photons lost energy and where did it go? |
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May 6 |
answered | Is the total energy of the universe constant? |
