Gravity: We might have been getting it wrong

Re:Gravity: We might have been getting it wrong by flatline on Friday January 24, 2020 @06:27PM (#22143357)

IANAP but I’m reasonably confident in asserting that GR is less wrong than Newtonian gravity, based on each models’ predictive power.

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Re:Gravity: We might have been getting it wrong by pdonis on Friday January 24, 2020 @06:31PM (#22143382)

> GR is no more or less wrong than Newtonian physics.

Then why does GR make more accurate predictions?

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Re:Gravity: We might have been getting it wrong by hudon on Friday January 24, 2020 @06:40PM (#22143412)

At low speeds relative to the speed of light, they have the same accuracy don't they? And in that case, the Newton model is simpler so more useful. At high speeds, it becomes inaccurate and then you need the other model.

So there is no global "right" or "wrong", just different measures of usefulness depending the problem constraints.

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Re:Gravity: We might have been getting it wrong by pdonis on Friday January 24, 2020 @07:50PM (#22143817)

> At low speeds relative to the speed of light, they have the same accuracy don't they?

GR is always more accurate, but the increased accuracy is not always needed; at low speeds relative to the speed of light the difference is often too small to matter in practical terms.

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Re:Gravity: We might have been getting it wrong by Koshkin on Friday January 24, 2020 @07:36PM (#22143723)

> there is no global "right" or "wrong"

You are wrong, so there is.

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Re:Gravity: We might have been getting it wrong by Supermancho on Friday January 24, 2020 @06:51PM (#22143479)

> At low speeds relative to the speed of light, they have the same accuracy don't they?

When measuring signal (ie radio, light, gravity) from slow speed perspectives, newtonian physics is not as accurate - https://futurism.com/newtonian-physics-vs-special-realtivity - Eg we actually need to account for it between gps sattelites and we do so from the perspective of GR as well as the recent evidence of gravity propogation being restricted to localization (ie roughly the speed of light)

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Re:Gravity: We might have been getting it wrong by hudon on Friday January 24, 2020 @07:09PM (#22143567)

Yup. And when you need to measure where artillery shells land, the GR model is overkill and you'll waste less time by using a Newtonian prediction. I think this proves my point?

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Re:Gravity: We might have been getting it wrong by kyralis on Friday January 24, 2020 @07:34PM (#22143704)

"Newtonion physics is a perfectly acceptable approximation in many circumstances" and "GR is less wrong than Newtonion physics" are not in conflict. Newtonion physics can absolutely be "more wrong" and "useful in many circumstances" at the same time- and in fact is!

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Re:Gravity: We might have been getting it wrong by bashinator on Friday January 24, 2020 @07:47PM (#22143797)

If your point is that they're both equally wrong, then no, I think you've disproven your own point. There are no circumstances in which Newtonian math produces better results than GR. That the latter is more complex is not relevant to the discussion of whether one is more accurate for a wider range of phenomena than the other.

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Re:Gravity: We might have been getting it wrong by pdonis on Friday January 24, 2020 @07:52PM (#22143830)

> I think this proves my point?

No, because "less accurate but in practical terms the difference can often be ignored" is not the same as "the same accuracy".

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Re:Gravity: We might have been getting it wrong by cma on Friday January 24, 2020 @07:45PM (#22143784)

So GR is more right in more scenarios and that makes it no more or less wrong?

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Re:Gravity: We might have been getting it wrong by withants on Saturday January 25, 2020 @02:30AM (#22145242)

i am a big fan of newtonian mechanics

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Re:Gravity: We might have been getting it wrong by krastanov on Friday January 24, 2020 @07:58PM (#22143870)

Besides the valid points of the other commenters, I have a nitpick: It is special relativity that deals with things near the speed of light, you do not need GR for it. GR is necessary to account for strong gravitational fields.

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