Okay so according to this link (https://briankoberlein.com/2014/08/01/bend-like-newton/):(adsbygoogle = window.adsbygoogle || []).push({});

"The catch is that the amount of bending predicted by Newton’s model is half of what Einstein’s model predicted."

(This is right after the changing diagram with light going past the sun in different theories and is describing the bending of light around the sun).

The author used the relativistic mass of light with Newton's formula. Although this may be self contradictory because special relativity may lead into general relativity and therefore away from Newton's gravitational formula (haven't gotten there yet), I will consider it as an assumption that one might be able to do this. My problem is that I would think the curving between Einstein and this breed of Newton wouldn't differ by such a high degree.

This is because when I consider the deviation between Einstein and Newton's formulas in terms of raw prediction, I usually think that Einstein's predictions really start to vary when either both masses are comparable to each other (in mass) or when they are a sizable radius away from each other. In the first case of variance I would suggest a case where there are two identical earths being attracted to each other rather than a satellite and the earth; the other case I think is pretty clear.

In the case cited by the article of the photon (light?), the photon's relativistic mass is relatively insignificant compared to the sun's, and the radius between the photon passing by the sun and the sun isn't really that large either (comparatively to something like Mercury, which I believe gets a sizable perihelion shift due to the distance between, with Mercury's mass as contributing factor) . Therefore I would predict that if one were to take the relativistic mass of a photon and plug it into Newton's formula the deviation of that from Einstein's formula would be negligible; certainly they wouldn't predict a curvature that is half of what Einstein would.

I know I probably shouldn't look at random websites for information, but I get the sense that the author is actually legitimate. I haven't actually taken general relativity yet and only base my analysis on my philosophy class on space and time and some geometric thinking. Also, I'm not even sure how you get relativistic mass for a photon, since it has zero rest mass so I can't use the relativistic formula for mass increase; I also am not sure I can use E=mc^2 because that may rely on relativistic mass for derivation (but this is really a side question).

I hope this question is not a burden at all; such that I can ask freely without worrying about causing anyone an unfortunate amount of extra trouble.

Thanks for reading,

Diwik

By the way I did look through the forum and while there were similar questions, I don't think they really answered what I was looking at. I hope that's right.

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# Bending of Light

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