Light speed and time in intergalactic space

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The discussion revolves around the effects of gravity on time as experienced by atomic clocks at different distances from Earth's gravitational center. It highlights that clocks further from gravity run faster, contradicting the initial assumption. The main question posed is whether light, traveling through intergalactic space, experiences time differently due to the lack of gravitational sources, potentially moving quickly over vast distances while appearing to take longer for observers. However, it is clarified that light does not experience time in a conventional sense, as it lacks a valid reference frame. The conversation emphasizes the complexities of time perception in relation to gravity and light's unique properties.
stilotto
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I have to start by saying that I don't have any formal training in this space (no pun intended). Still, I had a thought and I hope someone here might be able to tell me if it is valid.

I read an article on Physorg about an experiment which showed that two atomic clocks showed different times because they were varying distances from the Earth's gravitational center. The clock 30cm further from the center of gravity ran more slowly. This prompts my question.

When light is traveling through intergalactic space, does it experience time that moves more slowly relative to us because it is so far from any gravitational source? So could light sort of move over great distances in a short time for it, but a long time for us? My conception is that time is "dragged" near galaxies and "streamlined" in the more empty parts of the universe.

Thanks for looking at this. If it is ignorant or silly, just let me know. It is just something that occurred to me.
 
Space news on Phys.org
If memory serves, light (or photons) don't experience time.
 
stilotto said:
I have to start by saying that I don't have any formal training in this space (no pun intended). Still, I had a thought and I hope someone here might be able to tell me if it is valid.

I read an article on Physorg about an experiment which showed that two atomic clocks showed different times because they were varying distances from the Earth's gravitational center. The clock 30cm further from the center of gravity ran more slowly. This prompts my question.
You got that backwards the clock further away will run faster
The relationship follows the following relation.

\sqrt{1-\frac{2GM}{rc^2}}

This gives an answer that shows that time at the surface of the Earth runs at 0.9999999993
the rate that it does at a point in space totally removed from gravity. At this rate, it will take ~45 years for a 1 sec difference to accumulate between the clocks. This why you have to use atomic clocks to measure the difference, as they are very accurate.
When light is traveling through intergalactic space, does it experience time that moves more slowly relative to us because it is so far from any gravitational source? So could light sort of move over great distances in a short time for it, but a long time for us? My conception is that time is "dragged" near galaxies and "streamlined" in the more empty parts of the universe.

Thanks for looking at this. If it is ignorant or silly, just let me know. It is just something that occurred to me.

Another point that has already been made is that you can't really say how time passes for light because light itself doesn't have a valid reference frame.
 
I always thought it was odd that we know dark energy expands our universe, and that we know it has been increasing over time, yet no one ever expressed a "true" size of the universe (not "observable" universe, the ENTIRE universe) by just reversing the process of expansion based on our understanding of its rate through history, to the point where everything would've been in an extremely small region. The more I've looked into it recently, I've come to find that it is due to that "inflation"...

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