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: Now you might argue that if you were at rest at the center of the Earth, you'd be accelerated (in what direction?) faster than the ~9.8 m/s^2 at the surface. (I'd say you're wrong, but ok.) But that's not what the chart shows; it shows how fast you'd fall if you were at rest at the center of the Earth (and at other points) ''in these three models''. You seem to believe that none of these models reflect reality, but that's not only unsourced speculation but not particularly relevant to this article.
: [[User:CRGreathouse|CRGreathouse]]<small> ([[User talk:CRGreathouse|t]] | [[Special:Contributions/CRGreathouse|c]])</small> 01:41, 3 August 2024 (UTC)
:I think you might be light on general and special relativity and their effects.
:Acceleration is not about free fall speeds. Good grief, it's about time dilation.
:from phys.org
:"A trio of researchers in Denmark has calculated the relative ages of the surface of the Earth versus its core and has found that the core is 2.5 years younger than the crust. [it's likely considerably younger than even this]
:During one of his famous lectures at Caltech in the 1960's, Richard Feynman remarked that due to time dilation, the Earth's core is actually younger than its crust.
:General relativity suggests that really big objects, like planets and stars, actually warp the fabric of spacetime, which results in a gravitational pull capable of slowing down time. Thus, an object closer to Earth's center would feel a stronger pull—a clock set near the core would run slower than one placed at the surface, which means that the material that makes up the core is actually younger than the material that makes up the crust.
:In this new effort, the research trio ran the math to discover the actual number involved. They found that over the course of our planet's 4.5-billion-year history, the pull of gravity causes the core to be approximately 2.5 years younger than the crust—ignoring geological processes, of course." -phys.org
:As a thought experiment, consider the Earth as it is, with its stratified layers. Dense core with progressively less dense layers on top until you get to the crust and out into the atmosphere.
:Now take the moon and shrink it down to the size of a softball. Retain the mass of the moon, but now it’s close to a neutron star in density.
:Hold this ultra dense object on the surface of the Earth and let it fall. The deepest portion of Earth’s core, and the center of the softball sized moon will quickly displace the less dense materials between them and merge, with the little moon traveling the most distance and the core moving slightly for the merging.
:There might be some oscillation, but the dropped softball moon won’t be coming back up. Instead for the same volume, Earth’s surface acceleration is now over 10 m/s² due to being in a deeper gravity well because the mass of the Earth has increased an entire moon’s worth without gaining any significant volume.
:An acceleration tapering to zero at the core is a physics recipe for a hollow earth rather than the densest matter in the gravity well residing there.
:To that extent I dont have an issue with PREM's prediction on earth density because they used actual p and s waves to map the interior rather than a 300 year old notion of freefall at the core. [[Special:Contributions/2605:59C8:41D:2010:F9C0:7C09:A7A5:24DA|2605:59C8:41D:2010:F9C0:7C09:A7A5:24DA]] ([[User talk:2605:59C8:41D:2010:F9C0:7C09:A7A5:24DA|talk]]) 15:21, 22 August 2024 (UTC)
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