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Is gravity just entropy rising? Long-shot idea gets another look

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Re: Is gravity just entropy rising? Long-shot idea gets another look

#2
Space exists around things with mass. Also, above-absolute-zero temperatures cause particles to jump around randomly.

Now if there is "more space" around particle A, particle B will have a slightly higher statistical chance of randomly jumping closer to it, than farther.

Rinse-repeat. Gravity as we know it.

Re: Is gravity just entropy rising? Long-shot idea gets another look

#3

Space exists around things with mass. Also, above-absolute-zero temperatures cause particles to jump around randomly. Now if there is "more space" around particle A, particle B will have a slightly higher statistical chance of randomly jumping closer to it, than farther. Rinse-repeat. Gravity as we know it.

Sounds fun!

Would this imply that cold objects have weaker gravity?

Re: Is gravity just entropy rising? Long-shot idea gets another look

#4
We all know that life on Earth gets it's energy from the Sun.

But we also know that's an approximation we tell kids, really life gets low entropy photons from the Sun, does it's thing, and then emits high entropy infrared waste heat. Energy is conserved, while entropy increases.

But where did the Sun got it's low entropy photons to start with? From gravity, empty uniform space has low entropy, which got "scooped up" as the Sun formed.

EDIT: not sure why this is downvoted, is the explanation Nobel Physics laureate Roger Penrose gives: https://g.co/gemini/share/bd9a55da02b6

Re: Is gravity just entropy rising? Long-shot idea gets another look

#5
post #3

Space exists around things with mass. Also, above-absolute-zero temperatures cause particles to jump around randomly. Now if there is "more space" around particle A, particle B will have a slightly higher statistical chance of randomly jumping closer to it, than farther. Rinse-repeat. Gravity as we know it.

Sounds fun! Would this imply that cold objects have weaker gravity?

Isn't this something we already know from the mass–energy equivalence? In the same way that a nuclear reaction that produces heat must cost the object mass (and therefore gravitational pull)

Re: Is gravity just entropy rising? Long-shot idea gets another look

#6
Entropic gravity is a compelling framework. I think that most Physicists admit that it would be nice to believe that the yet unknown theory of everything is microscopic and quantum mechanical, and that the global and exquisitly weak force of gravity emerges from that theory as a sort of accounting error.

But there are so many potential assumptions baked into these theories that it's hard to believe when they claim, "look, Einstein's field equations."

Re: Is gravity just entropy rising? Long-shot idea gets another look

#8

We all know that life on Earth gets it's energy from the Sun. But we also know that's an approximation we tell kids, really life gets low entropy photons from the Sun, does it's thing, and then emits high entropy infrared waste heat. Energy is conserved, while entropy increases. But where did the Sun got it's low entropy photons to start with? From gravity, empty uniform space has low entropy, which got "scooped up"…

Your question fascinated me. Googling "where did the Sun got its low entropy" I also came across these explanations:

"Solar energy at Earth is low-entropy because all of it comes from a region of the sky with a diameter of half a degree of arc."

also, from another reply:

"Sunlight is low entropy because the sun is very hot. Entropy is essentially a measure of how spread out energy is. If you consider two systems with the same amount of thermal energy, then the one where that energy is more concentrated (low entropy) will be hotter."

https://physics.stackexchange.com/questions/796434/why-does-...

Probably it's a bit of both. I'm not sure I understand your hypothesis about the Sun scooping up empty, low-entropy space. Wasn't it formed from dusts and gases created by previous stellar explosions, i.e. the polar opposite of low entropy?

Re: Is gravity just entropy rising? Long-shot idea gets another look

#9

Space exists around things with mass. Also, above-absolute-zero temperatures cause particles to jump around randomly. Now if there is "more space" around particle A, particle B will have a slightly higher statistical chance of randomly jumping closer to it, than farther. Rinse-repeat. Gravity as we know it.

> particle B will have a slightly higher statistical chance of randomly jumping closer to it,

Why?

Also how do you explain acceleration due to gravity with that model. How do you explain solid objects?

Re: Is gravity just entropy rising? Long-shot idea gets another look

#10

Space exists around things with mass. Also, above-absolute-zero temperatures cause particles to jump around randomly. Now if there is "more space" around particle A, particle B will have a slightly higher statistical chance of randomly jumping closer to it, than farther. Rinse-repeat. Gravity as we know it.

sounds more like the reverse to me, movement away from denser areas (less space), so like water leaking out of a container.
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