This is my first post and I have no formal physics background, so please be gently with me.(adsbygoogle = window.adsbygoogle || []).push({});

I'm looking to get a better understanding of the effects of gravity on light and time. From what I've read (if I didn't misunderstand) a gravitational field will bend light to some degree. This in turn could make an object appear smaller to an observer who is further from the gravity field. I also understand that a clock close to the gravity field would appear to run slower then one outside of it. I'd be interested in opinions on the following thought.

Let's take 2 identical twins; exact same height, weight and age. Let's place one twin on the earth (North pole for arguments sake) and the other on the North pole of the moon. Now let's place an observer at a distance facing the twins and exactly equi-distant between them (seen from above as an equilateral triangle). We know the moon has less gravity then the earth, so here are my questions:

1. Assuming that the equi-distant observer is standing perfectly straight up and down in relation to the twins, would he appear to either of the twins to be leaning, or bending toward or away from the direction of the earth? And by this question I mean would this be caused by the Earth's gravity, light bending due to Earth's gravity, or both?

2. To the observer, assuming he had the ability to accurately measure the twins, would the Earth twin appear smaller then the Moon twin by any margin? If so, how much smaller?

3. Assuming the twins each had an extremely accurate clock with them that was perfectly synched at the beginning of this experiment, would there be a noticeable difference between the clock times when the twins call out their times to each other? (I know there is no such thing as instant signal travel, but for the sake of this question let's ignore that and assume they can instantly compare times with each other).

I'd appreciate any insight because while I find I'm able to understand a lot of this stuff, this is the subject that I can't seem to wrap my brain around very well.

Thanks!

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# Question on effects of gravity on light and time

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