Is Newton's Law of Gravitation Flawed?

In summary, there are several problems with Newton's law of universal gravitation. Firstly, it assumes that information can be transmitted at infinite speed, which goes against Einstein's theory of special relativity. Secondly, Newton's theory does not take into account the warping of space caused by massive objects, which Einstein's theory of general relativity addresses. Thirdly, there are flaws in the explanation of small particles bombarding Earth, Sun, and Moon, which Feynman's theory attempts to address but has been deemed quackery by experts. In conclusion, while Einstein's theory of gravity may not be complete, it is currently considered the most accurate explanation of gravity.
  • #1
PrincePhoenix
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What are the problems in Newton's law of universal gravitation? Please explain using simple physics if possible.
 
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  • #2
1. First off, it is an "action-at-a-distance" force, meaning that any change happening at one locality generates immediately an effect at other places.
That is, INFORMATION is spread at infinite speed throughout the universe.
Newton himself was deeply dissatisfied with this, and regarded his universal law of gravitation as an ad-hoc formula, that probably wasn't entirely right.

With Einstein's special relativity, physicists understood that information transmission speed CANNOT exceed the speed of light (a FINITE speed!), and thus, that in this crucial respect, Newton's law had to be false.

2. With Einstein's general theory of relativity, the interconnections of mass and space made for a fascinating solution:

Space is NOT like the rectangular box Newton envisaged it to be, within which matter resided without changing the box itself.

Rather, the presence of mass warps space(-time) itself, somewhat similar to that if you put a heavy ball on a linen sheet, you deform the linen sheet itself in that process.

3. Thus, if you are to calculate CORRECTLY the orbit for, say, a planet very close to a sun, the envisaged box structure of space, as Newton's theory presupposes, distorts your calculations because you neglect the spatial warping due to the presence of the sun.
This was, back in the 19th century, known as the anomaly of Mercury's orbit; the calculations simply didn't match the observations.

Einstein's theory of general relativity rectified that flaw.

4. Einstein's theory is entirely LOCAL, in the sense that a heavy object warps its local spatial region, and sends out information about its position&warp&mass at light speed (by means of yet unobserved gravitational waves).

5. In some sense, you could say that gravitation is no longer a force that acts directly upon an object; rather, gravitation acts upon space, and objects close to that warped region moves FREELY (i.e, without being influenced by a force), but in curved paths, rather than "straight lines".

Remember from Newton's first law that if an object is not under the influence of any force, it will move in a "straight line"; within general relativity, this holds as well, but because the space is warped/curved close to a massive object, that "straight line" (shortest distance between two points) will be a curved path instead (called a "geodesic")
 
  • #3
Thank you. That helped a lot.
 
  • #4
What is wrong with explanation that small particles bombarding Earth, Sun and Moon from all directions and from directions which they can't bombard (space between Earth and sun) apears smaller pressure than from those side from which they can bombard? Feynman was saying it's wrong because soon Earth or whatever planet should soon stop, but if those particles fast enough and enough small (like atom size) then really not nessasary some over explanation than that which was assumed by old civilisation which meaned Feynman. At least this theory which mentioned feynman shouldn't be such easy pushed away and at least mentioned in physical books in high school or 5-10 classes. How they can hide such things anyway?
edit: also inductiom of this small particles by sun the earth, erth inducting moon, and sun rotation about galaxy is inducted by rotation of this galaxy and so on.
 
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  • #5
vissarion.eu said:
What is wrong with explanation that small particles bombarding Earth, Sun and Moon from all directions and from directions which they can't bombard (space between Earth and sun) apears smaller pressure than from those side from which they can bombard? Feynman was saying it's wrong because soon Earth or whatever planet should soon stop, but if those particles fast enough and enough small (like atom size) then really not nessasary some over explanation than that which was assumed by old civilisation which meaned Feynman. At least this theory which mentioned feynman shouldn't be such easy pushed away and at least mentioned in physical books in high school or 5-10 classes. How they can hide such things anyway?

Because it is quackery.

Would you prefer we teach everything that hasn't shown to be valid in high school classes? Do you know how quickly we have to keep changing those books once we figure out they don't work? Do you know how many of such theories have been shown to be FALSE?

This "shadow" gravity effect has been discussed before, and it is off-topic to this thread. If you think there is a valid formalism for such a model, please use the IR forum, not here.

Zz.
 
  • #6
ZapperZ said:
Because it is quackery.

Would you prefer we teach everything that hasn't shown to be valid in high school classes? Do you know how quickly we have to keep changing those books once we figure out they don't work? Do you know how many of such theories have been shown to be FALSE?

This "shadow" gravity effect has been discussed before, and it is off-topic to this thread. If you think there is a valid formalism for such a model, please use the IR forum, not here.

Zz.

But from philosophycal or whatever point of view it's still very small probability that enshtein theory of gravity can be right even do not taking in count that it is not finished.
 
  • #7
vissarion.eu said:
But from philosophycal or whatever point of view it's still very small probability that enshtein theory of gravity can be right even do not taking in count that it is not finished.

Er... you are arguing physics based on PHILOSOPHY?

Since WHEN is physics done this way, and since when is physics ever thrown by philosophy? Is it because you lack the empirical verification?

Gravity may not be finished, but it certainly doesn't mean you are correct! That's the same tactic as that used by Intelligent Design folks. They have no evidence, so all they do is point to the apparent "holes" in Evolution.

Don't try this at home, or in this forum. You're just making your argument looks even more foolish.

Zz.
 

1. How did Newton come up with his law of gravitation?

Newton's law of gravitation was developed by Sir Isaac Newton in 1687. He was inspired by the fall of an apple from a tree, which led him to think about the force of gravity and how it affects objects in motion.

2. What is the formula for Newton's law of gravitation?

The formula for Newton's law of gravitation is F = G * (m1 * m2) / r2, where F is the force of gravity, G is the gravitational constant, m1 and m2 are the masses of the two objects, and r is the distance between them.

3. How does Newton's law of gravitation explain the motion of planets?

According to Newton's law of gravitation, every object in the universe exerts a force of attraction on every other object. This force is directly proportional to the masses of the objects and inversely proportional to the square of the distance between them. This explains the motion of planets around the sun, as the force of gravity between them keeps them in orbit.

4. Is Newton's law of gravitation still relevant today?

Yes, Newton's law of gravitation is still relevant and widely used today. It is the basis for understanding the motion of objects in our solar system and has been confirmed by numerous experiments and observations.

5. Can Newton's law of gravitation be applied to objects on Earth?

Yes, Newton's law of gravitation can be applied to objects on Earth, as it explains the force of gravity acting between any two objects with mass. However, for objects on Earth, the gravitational force is often dominated by other forces, such as friction and air resistance, making it less noticeable compared to the force of gravity between celestial bodies.

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