"There’s some kind of gas or some thermal system out there that we can’t see directly" - The Ether is back on the menu boys
Caloric. Dark matter. Cosmological constant.
We like placeholders for the unknown.
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
#12Space 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.
It sounds a bit like Le Sage's theory of gravity:
Re: Is gravity just entropy rising? Long-shot idea gets another look
#13We 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…
I read the gravity explanation for the sun low entropy in the "Road to Reality" book from Roger Penrose. Asked Gemini to summarize the argument (scroll to end)
Re: Is gravity just entropy rising? Long-shot idea gets another look
#14Like some sort of buoyancy?
Re: Is gravity just entropy rising? Long-shot idea gets another look
#15I don't get it.
To me, entropy is not a physical thing, but a measure of our imperfect knowledge about a system. We can only measure the bulk properties of matter, so we've made up a number to quantify how imperfect the bulk properties describe the true microscopic state of the system. But if we had the ability to zoom into the microscopic level, entropy would make no sense.
So I don't see how gravity or any other fundamental physical interaction could follow from entropy. It's a made-up thing by humans.
Re: Is gravity just entropy rising? Long-shot idea gets another look
#16Re: Is gravity just entropy rising? Long-shot idea gets another look
#17Space 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.
>Also, above-absolute-zero temperatures cause particles to jump around randomly.
Does it? A single free particle won't "jump around randomly". Thermal motion is plain Newtonian motion with an extremely high rate of collisions. There's nothing random about it (let's put quantum things aside for now).
Re: Is gravity just entropy rising? Long-shot idea gets another look
#18gravity=time
Re: Is gravity just entropy rising? Long-shot idea gets another look
#19I don't get it. To me, entropy is not a physical thing, but a measure of our imperfect knowledge about a system. We can only measure the bulk properties of matter, so we've made up a number to quantify how imperfect the bulk properties describe the true microscopic state of the system. But if we had the ability to zoom into the microscopic level, entropy would make no sense. So I don't see how gravity or any other fu…
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Re: Is gravity just entropy rising? Long-shot idea gets another look
#20Space 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?
It does, but because you have to divide the energy change by c^2, it is really really hard to detect it, and mostly overwhelmed by other effects of the heating/cooling.