Re:Scientists use an atomic clock to measure the height of a...
by sebtoast on Tuesday February 27, 2018 @05:14PM
(#16478512)
Thank you to all those who replied.
At the top of the article you linked there's the: "This article is about time dilation due to relative gravity. For time dilation due to relative velocity, see Relative velocity time dilation."
I didn't know there were "two forms" of time dilation, knowing what to search for helps a lot.
Thanks again.
Re:Scientists use an atomic clock to measure the height of a...
by dredmorbius on Tuesday February 27, 2018 @08:27PM
(#16479894)
On the "centre of Earth's gravity well" bit: what is the net effect of the fact that inside a sphere, the net gravitational attraction depends on the amount, distance, and vector of the gravitational mass in question, and that whilst inside a sphere at any point beneath its surface the net gravitational attraction varies.
In the case of the Earth, it actually increases to a certain depth, then falls as one approaches the centre (or would if one could; imagine, say, the neutrino version of yourself). My first thought was that the associated time dilation would follow a similar trend, though thinking this through, I'm not certain, though I'm leaning toward your answer above as not being accurate.
However, time passes slower the deeper one gets into a gravity well. The center of the Earth is the center of Earth's gravity well, so the closer to it you are, the slower your clock ticks.
More info: https://en.wikipedia.org/wiki/Gravitational_time_dilation