# Thread: Does gravity create endless energy?

1. Probably wrong about this, but objects being pulled towards an object have kinetic energy. Unless gravity runs out of its pull, then it would create endless energy.
V

2.

3. The increase in kinetic energy of an object as it falls towards a gravitational source comes from the energy-equivalent of the mass of the object.

4. Question: If a sphere made of a material you could pass through had gravity at its center, would an item just be pulled to its center or would it be pulled to the other side in a back-and-forth motion until it settles in the center?

5. Originally Posted by Blahgory
Question: If a sphere made of a material you could pass through had gravity at its center, would an item just be pulled to its center or would it be pulled to the other side in a back-and-forth motion until it settles in the center?
That all depends on what you mean by "a material you could pass through".

If you are falling through a material that would slow your fall, then you would fall past the centre and then back and forth until you settled at the centre.

If, on the other hand, you were falling down a tube through the sphere, and that tube were evacuated of air so there was nothing to slow your fall, you would fall all the way through to the other side of the sphere, and then fall back through again to the other side, ad infinitum, going back and forth without ever settling at the centre.

6. In a gravitational well, you could well deal with infinite energy, depending on your model.

7. Originally Posted by SpeedFreek
Originally Posted by Blahgory
Question: If a sphere made of a material you could pass through had gravity at its center, would an item just be pulled to its center or would it be pulled to the other side in a back-and-forth motion until it settles in the center?
That all depends on what you mean by "a material you could pass through".

True. It only depends on electrostatic particles. There is apparently, plenty matter in this universe we can't even measure.

A good example is Axions. They should pass through solid matter everyday... if they exist. There is some evidence they might.

8. Originally Posted by SpeedFreek
Originally Posted by Blahgory
Question: If a sphere made of a material you could pass through had gravity at its center, would an item just be pulled to its center or would it be pulled to the other side in a back-and-forth motion until it settles in the center?
That all depends on what you mean by "a material you could pass through".

If you are falling through a material that would slow your fall, then you would fall past the centre and then back and forth until you settled at the centre.

If, on the other hand, you were falling down a tube through the sphere, and that tube were evacuated of air so there was nothing to slow your fall, you would fall all the way through to the other side of the sphere, and then fall back through again to the other side, ad infinitum, going back and forth without ever settling at the centre.
Could you harness that somehow in a way that doesn't slow the object down very much, and have an energy source that would last for a long time?

9. Originally Posted by SowZ37
Originally Posted by SpeedFreek
Originally Posted by Blahgory
Question: If a sphere made of a material you could pass through had gravity at its center, would an item just be pulled to its center or would it be pulled to the other side in a back-and-forth motion until it settles in the center?
That all depends on what you mean by "a material you could pass through".

If you are falling through a material that would slow your fall, then you would fall past the centre and then back and forth until you settled at the centre.

If, on the other hand, you were falling down a tube through the sphere, and that tube were evacuated of air so there was nothing to slow your fall, you would fall all the way through to the other side of the sphere, and then fall back through again to the other side, ad infinitum, going back and forth without ever settling at the centre.
Could you harness that somehow in a way that doesn't slow the object down very much, and have an energy source that would last for a long time?
Not really. Conservation of energy would demand that for every Joule you extract from this motion, the energy of the object would reduce by one Joule.

The motion is a kind of harmonic motion, in that energy is swapped continuously between kinetic and gravitational potential. It is all potential at the extremes of the motion and all kinetic as it passes through the centre, and everywhere in between it is combination of the two. (It is not Simple Harmonic Motion though, since the restoring force is not proportional to the displacement.)

Extracting energy from this would be essentially the same as hydroelectric power generation: conversion of gravitational potential (or kinetic energy obtained from that) into electrical energy.

10. Lets not dismiss the idea of endless energy if the energy mass equilacence prevents endless energy then an object has to stop having gravity eventually or else it is endless.

11. Originally Posted by frumpydolphin
Lets not dismiss the idea of endless energy if the energy mass equilacence prevents endless energy then an object has to stop having gravity eventually or else it is endless.
This seems garbled. The concept of gravitational potential energy has little to do with the equivalence between energy and mass.

Work done (=energy expended) = force x distance moved under the influence of that force. Expressing this in standard units, Joules = Newtons x metres

For example, on the surface of the Earth a 1kg mass weighs 9.8 Newtons. If this falls a distance of 1m towards the centre of the Earth it can do 9.8 Joules of work.

E=mc² does not help much in this example.

12. Originally Posted by frumpydolphin
Lets not dismiss the idea of endless energy if the energy mass equilacence prevents endless energy then an object has to stop having gravity eventually or else it is endless.
No, let's dismiss the idea of endless energy. Even if we correct your muddle (I am sorry that I cannot decode what you meant, but it seems hopelessly wrong anyway), Noether's first theorem puts conservation of energy on rather solid footing. She connected various conservation laws to corresponding symmetries in other physical laws. Unless you have a method for violating these symmetries, you will not be able to consider -- let alone achieve -- endless energy.

Energy conservation is implied by time invariance of physical laws.

Momentum conservation is also implied by translational invariance of physical laws.

Finally, angular momentum conservation is similarly implied by rotational invariance of physical laws.

Noether's theorem saves us a lot of time by showing the futility of, say, looking for a magic arrangement of magnets, or converting mass into energy in a gravitational field, as a way to create endless energy. The symmetries are not violated in such cases, so we know immediately that endless energy will not result.

13. That is what you call a closed mind thinker, which suggests you wont ever come up with something smart or out of the ordinary.

14. Originally Posted by frumpydolphin
That is what you call a closed mind thinker, which suggests you wont ever come up with something smart or out of the ordinary.
That statement is glib rubbish, typical of people who have no understanding of science and how it distinguishes itself from fantasy.

In science, nobody overthrows the existing theory until such time as there is compelling observational evidence that this is required. Any new hypothesis has to be tested against the observational facts. It has to not only account for the new but must also continue to explain the old.

You do not just go around dreamily hoping that laws you don't like might be untrue. That is not science, it is poor quality science fiction. Quality control is crucial in scientific thought and the challenge is always observational evidence. That is what Feynman meant by his remark "Keep an open mind ,but not so open your brains fall out".

15. Maybe if you tried to understand what im saying you could tell me why its wrong instead of just saying it's silly. Id say this is the more logical thing to do.

16. Originally Posted by frumpydolphin
That is what you call a closed mind thinker, which suggests you wont ever come up with something smart or out of the ordinary.
Why do cranks feel it's better to be original than to be correct?

17. Well since no ones going to consider my theory might as well give up.

18. Originally Posted by frumpydolphin
Lets not dismiss the idea of endless energy if the energy mass equilacence prevents endless energy then an object has to stop having gravity eventually or else it is endless.
Gravity may always have potential energy, to harness the energy, if I remember correctly you need to harness the kinetic energy. The use of energy, normally means overcoming friction. To produce energy, you must create friction. Energy can not be created or destroyed, even in a perfectly designed system the net would be zero.

19. Originally Posted by frumpydolphin
Well since no ones going to consider my theory might as well give up.
No one??? Three people replied to your idea:

Originally Posted by KJW
The increase in kinetic energy of an object as it falls towards a gravitational source comes from the energy-equivalent of the mass of the object.
Originally Posted by exchemist
Originally Posted by frumpydolphin
Lets not dismiss the idea of endless energy if the energy mass equilacence prevents endless energy then an object has to stop having gravity eventually or else it is endless.
This seems garbled. The concept of gravitational potential energy has little to do with the equivalence between energy and mass.

Work done (=energy expended) = force x distance moved under the influence of that force. Expressing this in standard units, Joules = Newtons x metres

For example, on the surface of the Earth a 1kg mass weighs 9.8 Newtons. If this falls a distance of 1m towards the centre of the Earth it can do 9.8 Joules of work.

E=mc² does not help much in this example.
Originally Posted by tk421
Originally Posted by frumpydolphin
Lets not dismiss the idea of endless energy if the energy mass equilacence prevents endless energy then an object has to stop having gravity eventually or else it is endless.
No, let's dismiss the idea of endless energy. Even if we correct your muddle (I am sorry that I cannot decode what you meant, but it seems hopelessly wrong anyway), Noether's first theorem puts conservation of energy on rather solid footing. She connected various conservation laws to corresponding symmetries in other physical laws. Unless you have a method for violating these symmetries, you will not be able to consider -- let alone achieve -- endless energy.

Energy conservation is implied by time invariance of physical laws.

Momentum conservation is also implied by translational invariance of physical laws.

Finally, angular momentum conservation is similarly implied by rotational invariance of physical laws.

Noether's theorem saves us a lot of time by showing the futility of, say, looking for a magic arrangement of magnets, or converting mass into energy in a gravitational field, as a way to create endless energy. The symmetries are not violated in such cases, so we know immediately that endless energy will not result.
Just because no one supported your idea, it doesn't mean it wasn't considered.

20. I'll be honest, here. I won't generally give theories an honest go if they aren't proposed by PhDs. Not out of elitism, but because I have limited time and many, many theories that I am unfamiliar with. If I am going to spend my energy, (it takes a good deal of intellectual energy to truly consider a theory and try to take its implications to their logical conclusions,) I am probably going to spend it on a more widely accepted/debated theory. I don't think this makes me close minded.

21. A piece of friendly advice, if you want your hypotheses to be taken seriously, you need three things. First, you need to show that you understand the existing theories. Second, you need to show your hypothesis can be quantified (that is measured and tested). And three, you need to show that you've made some attempt to falsify your own hypothesis, either by doing experiments yourself or by looking up old experiments and comparing results. Why?

First, existing theories are accepted for a reason. Namely, they work. That's about it really. They work and continue to work despite every scientist in the world trying to break them. (Doing so, rigorously and repeatably, would mean a Nobel prize, a nice paycheck and massive renown.) If you can't be bothered to understand the existing theories, you probably won't understand why your hypothesis might fail, or other people's examples of why it would fail.

Second, if your hypothesis can't be tested, it isn't science. If it can't be quantified, it usually can't be tested, especially in physics. "Things move towards heavy things" is something like a description of gravity, but you couldn't use it for anything. You would never be able to plot a course for a probe and expect it to get anywhere close to it's intended destination. "Charge moves from positive to negative" is not enough to build a modern computer.

Third, you should be your own worst critic because no one else is going to be particularly nice about poking holes in your hypotheses. That's just the way science works. The theories that are accepted are those that still work after everyone's thrown everything they've got at breaking them. You should go ahead and be the first to try.

(This isn't really an exhaustive list either. With these three things, you could probably stir up some interest on the forum, but alone they wouldn't be enough to get a paper published. There's also more reasons why each of these are important than I've listed.)

22. Originally Posted by frumpydolphin
Maybe if you tried to understand what im saying you could tell me why its wrong instead of just saying it's silly. Id say this is the more logical thing to do.
Several people have already given you cogent, well-reasoned arguments for why it's wrong. It seems that you didn't bother to read any of them. Why is that? Are you sincerely interested in science, or are you looking for magic?

Instead of pouting like an infant who has been denied his rattle, it's far better to study why your dream of endless energy is simply disallowed by what we know. Noether's theorem tells us that a necessary ingredient would be to find a way to break the symmetries which underlie energy conservation. If you can't do that, you can't violate energy conservation. Period. End of story. Infinite imagination will not help. Wishing really, really hard won't, either. "If wishes were horses, beggars would ride."

23. Originally Posted by keeseguy
Originally Posted by frumpydolphin
Lets not dismiss the idea of endless energy if the energy mass equilacence prevents endless energy then an object has to stop having gravity eventually or else it is endless.
Gravity may always have potential energy, to harness the energy, if I remember correctly you need to harness the kinetic energy. The use of energy, normally means overcoming friction. To produce energy, you must create friction. Energy can not be created or destroyed, even in a perfectly designed system the net would be zero.
No this is not right. It's true (for all practical purposes at least) that energy cannot be created nor destroyed, but friction has nothing to do with energy conversion.

Energy can also be converted from one form to another without utilising kinetic energy. For example, plant photosynthesis converts light energy to chemical energy and a thermocouple converts heat to electrical energy, in both cases doing so without kinetic energy coming into the picture.

24. Originally Posted by frumpydolphin
Well since no ones going to consider my theory might as well give up.
Frumpydolphin, it is not at all clear what your theory is. You seem to be having trouble expressing yourself scientifically. I have to say that your latest remarks suggest the reason for this may be that you do not know how to think in a sufficiently precise way to conduct a scientific discussion. If you can sharpen up what you mean, so we can have something to get hold of, then maybe you will get a more sympathetic hearing.

Speaking personally, I am always very keen indeed to help people's understanding of science. But I have no time for people who come here talking what seems to be badly expressed, vague nonsense, and then attempting to rubbish trained scientists from a position of total ignorance.

It's up to you.

25. Well I geuss i'll do some testing and as soon as it can be supported ill be back.

26. Originally Posted by exchemist
Originally Posted by frumpydolphin
Well since no ones going to consider my theory might as well give up.
Frumpydolphin, it is not at all clear what your theory is. You seem to be having trouble expressing yourself scientifically. I have to say that your latest remarks suggest the reason for this may be that you do not know how to think in a sufficiently precise way to conduct a scientific discussion. If you can sharpen up what you mean, so we can have something to get hold of, then maybe you will get a more sympathetic hearing.

Speaking personally, I am always very keen indeed to help people's understanding of science. But I have no time for people who come here talking what seems to be badly expressed, vague nonsense, and then attempting to rubbish trained scientists from a position of total ignorance.

It's up to you.
the top comment is my idea.

27. Originally Posted by frumpydolphin
Originally Posted by exchemist
Originally Posted by frumpydolphin
Well since no ones going to consider my theory might as well give up.
Frumpydolphin, it is not at all clear what your theory is. You seem to be having trouble expressing yourself scientifically. I have to say that your latest remarks suggest the reason for this may be that you do not know how to think in a sufficiently precise way to conduct a scientific discussion. If you can sharpen up what you mean, so we can have something to get hold of, then maybe you will get a more sympathetic hearing.

Speaking personally, I am always very keen indeed to help people's understanding of science. But I have no time for people who come here talking what seems to be badly expressed, vague nonsense, and then attempting to rubbish trained scientists from a position of total ignorance.

It's up to you.
the top comment is my idea.
You mean " Probably wrong about this, but objects being pulled towards an object have kinetic energy. Unless gravity runs out of its pull, then it would create endless energy." ?

Well the first part is correct in that anything in motion has kinetic energy. The second part is not right, since gravity can only be a source of energy in this way so long as there are more objects to be pulled in - which eventually entails putting energy in, against gravity, to get them them back up there, once you have run out of objects.

Probably the closest we get to this in current practice is hydroelectric power. A hydroelectric generating station can extract energy from falling water, so long as there is water in the reservoir. The clever part about this is that the sun provides the energy to return the water back to the top, via rainfall returning water evaporated from the oceans. One could argue (slightly pedantically) that hydroelectricity is really using solar power, with the water as an intermediate "working fluid".

Anyway, that is my best reply based on what was in your OP. But I'm happy to discuss further if this is not what you had in mind.

28. I plan to research this topic for more information...ill be back!

29. Originally Posted by frumpydolphin
Jolly good. Don't get caught in any fishing nets on the way.

30. Would tidal hydro-generation fall into this category? Not to stir a hornets nest.

31. Originally Posted by keeseguy
Would tidal hydro-generation fall into this category? Not to stir a hornets nest.
Well not exactly, as that is a rise and fall of water caused by the gravity of the moon and sun, which results in a current that can be intercepted and used to extract energy. Whereas the source of energy in conventional hydroelectric power is solar heat. But tidal power certainly is an example of gravitational energy being harnessed for electric power. In this case, the power extracted contributes to reducing ever so slightly the kinetic energy of the orbiting celestial bodies. So in this case you might say the gravitational effect is a medium for extracting kinetic energy of orbital motion of the moon round the Earth and theEarth round the sun.

32. Originally Posted by KJW
The increase in kinetic energy of an object as it falls towards a gravitational source comes from the energy-equivalent of the mass of the object.
Is that like saying gravitational potential energy is stored as mass?

33. Originally Posted by Robittybob1
Originally Posted by KJW
The increase in kinetic energy of an object as it falls towards a gravitational source comes from the energy-equivalent of the mass of the object.
Is that like saying gravitational potential energy is stored as mass?
More accurate to say it is stored as work and released as work.

34. Originally Posted by dan hunter
Originally Posted by Robittybob1
Originally Posted by KJW
The increase in kinetic energy of an object as it falls towards a gravitational source comes from the energy-equivalent of the mass of the object.
Is that like saying gravitational potential energy is stored as mass?
More accurate to say it is stored as work and released as work.
What is work then? Work is stored as?

35. Originally Posted by frumpydolphin
Probably wrong about this, but objects being pulled towards an object have kinetic energy. Unless gravity runs out of its pull, then it would create endless energy.
V

There is a limit to how much energy you can get from a falling object even if it falls from an infinite distance. That works to ~ 17.41 kwh per kilogram of falling mass at the surface of the Earth. So, unless you have an endless supply of falling objects, you can not have an endless supply of energy.

36. Originally Posted by frumpydolphin
yes. you are wrong.

Originally Posted by frumpydolphin
Originally Posted by frumpydolphin
Well I geuss i'll do some testing and as soon as it can be supported ill be back.
so, what testing have you done? what info have you gotten from your research?

37. Originally Posted by Chucknorium
Originally Posted by frumpydolphin
yes. you are wrong.

Originally Posted by frumpydolphin
Originally Posted by frumpydolphin
Well I geuss i'll do some testing and as soon as it can be supported ill be back.
so, what testing have you done? what info have you gotten from your research?
All he has to do is build a perpetual motion machine. Easy!

38. Originally Posted by Robittybob1
Originally Posted by Chucknorium
Originally Posted by frumpydolphin
yes. you are wrong.

Originally Posted by frumpydolphin
Originally Posted by frumpydolphin
Well I geuss i'll do some testing and as soon as it can be supported ill be back.
so, what testing have you done? what info have you gotten from your research?
All he has to do is build a perpetual motion machine. Easy!
It seems easy on paper to some. Say your invention is already above 98% efficient. All you need is another 2% and you're done.

That's a paraphrase of a conversation I once had with an "overunity" enthusiast. It accurately captures the quality of his reasoning.

39. Originally Posted by tk421
Originally Posted by Robittybob1
Originally Posted by Chucknorium
Originally Posted by frumpydolphin
yes. you are wrong.

Originally Posted by frumpydolphin
Originally Posted by frumpydolphin
Well I geuss i'll do some testing and as soon as it can be supported ill be back.
so, what testing have you done? what info have you gotten from your research?
All he has to do is build a perpetual motion machine. Easy!
It seems easy on paper to some. Say your invention is already above 98% efficient. All you need is another 2% and you're done.

That's a paraphrase of a conversation I once had with an "overunity" enthusiast. It accurately captures the quality of his reasoning.
that pesky 2nd Law of Thermodynamics always gets in the way . . . .

40. I don't know what the answer is, but my guess is that it involves magnets.

41. Originally Posted by Flick Montana
I don't know what the answer is, but my guess is that it involves magnets.
Even the best machine magnet machines just don't run on their own.

42. Originally Posted by Flick Montana
I don't know what the answer is, but my guess is that it involves magnets.
Yes, and Tesla will probably get into the act somehow……….or pendulums……...

43. Originally Posted by Robittybob1
Originally Posted by Flick Montana
I don't know what the answer is, but my guess is that it involves magnets.
Even the best machine magnet machines just don't run on their own.
That's just because you're a mainstream close-minded scientist. Think outside the box. They laughed at Wegener, too.

44. Originally Posted by Flick Montana
Originally Posted by Robittybob1
Originally Posted by Flick Montana
I don't know what the answer is, but my guess is that it involves magnets.
Even the best machine magnet machines just don't run on their own.
That's just because you're a mainstream close-minded scientist. Think outside the box. They laughed at Wegener, too.
Who was he? Are you talking about http://en.wikipedia.org/wiki/Alfred_Wegener ?

45. Ive figured that because when gravity pulls something it is using the objects mass to create energy....so you would need endless mass.

46. Originally Posted by frumpydolphin
Ive figured that because when gravity pulls something it is using the objects mass to create energy....so you would need endless mass.
Exactly.

47. Originally Posted by Robittybob1
Originally Posted by Flick Montana
Originally Posted by Robittybob1
Originally Posted by Flick Montana
I don't know what the answer is, but my guess is that it involves magnets.
Even the best machine magnet machines just don't run on their own.
That's just because you're a mainstream close-minded scientist. Think outside the box. They laughed at Wegener, too.
Who was he? Are you talking about Alfred Wegener - Wikipedia, the free encyclopedia ?
Yes.

He's my personal favorite scientist.

48. Originally Posted by Flick Montana
He's my personal favorite scientist.
best bumper sticker i ever saw (and i only saw it once) was "Stop Continental Drift!"

49. Originally Posted by frumpydolphin
Ive figured that because when gravity pulls something it is using the objects mass to create energy....so you would need endless mass.
Also, gravitational pull cannot be endless because, at some point, the two objects will collide. (Or settle into a stable orbit.)

50. Originally Posted by Chucknorium
best bumper sticker i ever saw (and i only saw it once) was "Stop Continental Drift!"
Go West

51. Originally Posted by Strange
Originally Posted by Chucknorium
best bumper sticker i ever saw (and i only saw it once) was "Stop Continental Drift!"
Go West
thanks for that. good one. it would probably slow down the drift but by such a small amount that couldn't possibly be measured.

52. Originally Posted by SowZ37
I'll be honest, here. I won't generally give theories an honest go if they aren't proposed by PhDs. Not out of elitism, but because I have limited time and many, many theories that I am unfamiliar with. If I am going to spend my energy, (it takes a good deal of intellectual energy to truly consider a theory and try to take its implications to their logical conclusions,) I am probably going to spend it on a more widely accepted/debated theory. I don't think this makes me close minded.
Do you mean actual Ph.D's or the forum rank?

53. Originally Posted by ajarjour
Originally Posted by SowZ37
I'll be honest, here. I won't generally give theories an honest go if they aren't proposed by PhDs. Not out of elitism, but because I have limited time and many, many theories that I am unfamiliar with. If I am going to spend my energy, (it takes a good deal of intellectual energy to truly consider a theory and try to take its implications to their logical conclusions,) I am probably going to spend it on a more widely accepted/debated theory. I don't think this makes me close minded.
Do you mean actual Ph.D's or the forum rank?
Actual PhDs. I'll listen to a cool idea some Joe Shmoe has, but an actual scientific theory proposed by a non-professional, I will invest very little intellectual energy into.

54. I'd at least give a once over to some random ideas if they could at least show that they've followed the scientific method. Of course most random idea posters here seem to be willfully ignorant of it. (The ones who aren't will often have mistakes pointed out, accept the corrections and move on, so you just don't hear as much from them.)

55. In light of the apparent horde of people proposing pseudoscience on this forum, that seems like a wise plan for the internet. In real life however, (especially in the academic setting) people who are more educated (i.e. said Ph.Ds) have a responsibility to educate those less educated (grad students, or undergrads like me). Often, this can consist of the student proposing explanations for things (which are wrong most of the time) not because they expect to contribute to the scientific body of knowledge, but because it is an effective way to learn. I propose explanations for things all the time to the professors I study and work under, and they take the time to explain either a) how I am wrong or b) where I can find the work of thought of my "original" idea 200 years ago. If some day I am fortunate enough to end up in a position where I am called upon to produce original scientific research, I think this sort of practice will be helpful. Of course, I don't think that applies here, the OP seems either horribly confused or to be trolling, but just a thought for real life.

56. Originally Posted by ajarjour
In light of the apparent horde of people proposing pseudoscience on this forum, that seems like a wise plan for the internet. In real life however, (especially in the academic setting) people who are more educated (i.e. said Ph.Ds) have a responsibility to educate those less educated (grad students, or undergrads like me). Often, this can consist of the student proposing explanations for things (which are wrong most of the time) not because they expect to contribute to the scientific body of knowledge, but because it is an effective way to learn. I propose explanations for things all the time to the professors I study and work under, and they take the time to explain either a) how I am wrong or b) where I can find the work of thought of my "original" idea 200 years ago. If some day I am fortunate enough to end up in a position where I am called upon to produce original scientific research, I think this sort of practice will be helpful. Of course, I don't think that applies here, the OP seems either horribly confused or to be trolling, but just a thought for real life.
That's sensible. I, however, am in a field where the closest I come to professional science is maybe working on a sci-fi set sometime, so I have limited time to keep up with science as a sort of hobby. Since I can't devote a full time job to it, I limit serious consideration to ideas that PhDs present.

57. Originally Posted by ajarjour
In light of the apparent horde of people proposing pseudoscience on this forum, . . .
It sure seems that way sometimes.

I wonder if anyone has ever seen a hypothesis proposed on a science forum that actually became a scientific method theory?

58. What causes gravity? We do not know.
Is gravity push or pull? We do not know.
Is gravity universal? We do not know.

Gravity at the local level (say within our solar system and to some point in the Milky Way) can be treated as universal, but is really one of the unsolved mysteries, yet is so basic.

59. Originally Posted by JoeSixPack
What causes gravity? We do not know.
Is gravity push or pull? We do not know.
Is gravity universal? We do not know.

Gravity at the local level (say within our solar system and to some point in the Milky Way) can be treated as universal, but is really one of the unsolved mysteries, yet is so basic.
We have working theories, but we don't know for sure why gravity functions. But it is pretty predictable. We know how it functions better, I think, than you are implying. Even if there are multiple explanations on why it functions, how it functions is pretty observable.

60. Originally Posted by SowZ37
Originally Posted by JoeSixPack
What causes gravity? We do not know.
Is gravity push or pull? We do not know.
Is gravity universal? We do not know.

Gravity at the local level (say within our solar system and to some point in the Milky Way) can be treated as universal, but is really one of the unsolved mysteries, yet is so basic.
We have working theories, but we don't know for sure why gravity functions. But it is pretty predictable. We know how it functions better, I think, than you are implying. Even if there are multiple explanations on why it functions, how it functions is pretty observable.
At an engineering level terrestrially, and even out to the edge of the solar system (and probably quite a ways beyond), we have a good handle on it. For engineers, it is very predictable.

61. Originally Posted by JoeSixPack
What causes gravity? We do not know.
Is gravity push or pull? We do not know.
Is gravity universal? We do not know.
The curvature of spacetime causes gravity. Mass and energy cause the curvature of spacetime.

Gravity is definitely not push. It has been mathematically shown that push gravity cannot reproduce what we observe in nature. Gravity isn't exactly pull either, but pull gravity (i.e. Newtonian gravity) is at least a very good approximation of what we observe. (It works very well except in regions of very high gravity.)

We can look at light that's several billion years old and the galaxies we see in that light still spin just the same as the galaxies today do. While it's possible there are some slight differences, gravity obviously still existed then. And we can see such galaxies in every direction we look, so it obviously exists everywhere as well.

62. <unnecessary post>

63. Originally Posted by MagiMaster

The curvature of spacetime causes gravity. Mass and energy cause the curvature of spacetime.
And what is spacetime curvature in physical terms?

Originally Posted by MagiMaster
Gravity is definitely not push. It has been mathematically shown that push gravity cannot reproduce what we observe in nature. Gravity isn't exactly pull either, but pull gravity (i.e. Newtonian gravity) is at least a very good approximation of what we observe. (It works very well except in regions of very high gravity.)
Any time after Lord Rayleigh expressed his opinion? Mathematically it reduces to the same formula F=Gm1m2/r^2, so how do we discriminate?

Originally Posted by MagiMaster
We can look at light that's several billion years old and the galaxies we see in that light still spin just the same as the galaxies today do. While it's possible there are some slight differences, gravity obviously still existed then. And we can see such galaxies in every direction we look, so it obviously exists everywhere as well.
Again, if it is universal, and "magic" (i.e., action at a distance or attractive), or if it is push (due to "ultramundane corpuscles"). But if it is more a phenomenon of an fluidic like ether, then is an effect, and not a fundamental force in itself (i.e., ala George Stokes). I know this is considered very unlikely now, but considering we have no theory explaining mechanistically what causes gravity (vs. being able to predict its effects locally, which we can do very well), we need to keep an open mind.

64. Originally Posted by JoeSixPack
Originally Posted by MagiMaster

The curvature of spacetime causes gravity. Mass and energy cause the curvature of spacetime.
And what is spacetime curvature in physical terms?

Originally Posted by MagiMaster
Gravity is definitely not push. It has been mathematically shown that push gravity cannot reproduce what we observe in nature. Gravity isn't exactly pull either, but pull gravity (i.e. Newtonian gravity) is at least a very good approximation of what we observe. (It works very well except in regions of very high gravity.)
Any time after Lord Rayleigh expressed his opinion? Mathematically it reduces to the same formula F=Gm1m2/r^2, so how do we discriminate?

Originally Posted by MagiMaster
We can look at light that's several billion years old and the galaxies we see in that light still spin just the same as the galaxies today do. While it's possible there are some slight differences, gravity obviously still existed then. And we can see such galaxies in every direction we look, so it obviously exists everywhere as well.
Again, if it is universal, and "magic" (i.e., action at a distance or attractive), or if it is push (due to "ultramundane corpuscles"). But if it is more a phenomenon of an fluidic like ether, then is an effect, and not a fundamental force in itself (i.e., ala George Stokes). I know this is considered very unlikely now, but considering we have no theory explaining mechanistically what causes gravity (vs. being able to predict its effects locally, which we can do very well), we need to keep an open mind.
How do you manage to pack so much crank misconceptions in your posts?

65. Originally Posted by JoeSixPack
Again, if it is universal, and "magic" (i.e., action at a distance or attractive)
I'll leave it to the people who are better versed in the details to, well, deal with the details, but I can comment on this. Spacetime curvature isn't magic action at a distance. When you put a bowling ball in the middle of a trampoline, the fabric takes time to settle into its new shape and then other objects on that trampoline will start rolling towards the bowling ball. Now, that's only a rough analogy, but changes in the curvature of spacetime (from the movement of mass for example) do take time to propagate. (As it happens, they propagate at the speed of light.)

Edit: Also, when you (and people like you) refer to a mechanical explanation, I really have no idea what you mean. Do you mean something like a universe built out of little springs and gears?

66. Originally Posted by MagiMaster
Originally Posted by JoeSixPack
Again, if it is universal, and "magic" (i.e., action at a distance or attractive)
I'll leave it to the people who are better versed in the details to, well, deal with the details, but I can comment on this. Spacetime curvature isn't magic action at a distance. When you put a bowling ball in the middle of a trampoline, the fabric takes time to settle into its new shape and then other objects on that trampoline will start rolling towards the bowling ball. Now, that's only a rough analogy, but changes in the curvature of spacetime (from the movement of mass for example) do take time to propagate. (As it happens, they propagate at the speed of light.)
Action at a distance (magic) only refers to pull gravity. Curvature of spacetime is a mathematical concept, but ultimately needs to be translated into some physical mechanism.

67. Originally Posted by xyzt
Originally Posted by JoeSixPack
Originally Posted by MagiMaster

The curvature of spacetime causes gravity. Mass and energy cause the curvature of spacetime.
And what is spacetime curvature in physical terms?

Originally Posted by MagiMaster
Gravity is definitely not push. It has been mathematically shown that push gravity cannot reproduce what we observe in nature. Gravity isn't exactly pull either, but pull gravity (i.e. Newtonian gravity) is at least a very good approximation of what we observe. (It works very well except in regions of very high gravity.)
Any time after Lord Rayleigh expressed his opinion? Mathematically it reduces to the same formula F=Gm1m2/r^2, so how do we discriminate?

Originally Posted by MagiMaster
We can look at light that's several billion years old and the galaxies we see in that light still spin just the same as the galaxies today do. While it's possible there are some slight differences, gravity obviously still existed then. And we can see such galaxies in every direction we look, so it obviously exists everywhere as well.
Again, if it is universal, and "magic" (i.e., action at a distance or attractive), or if it is push (due to "ultramundane corpuscles"). But if it is more a phenomenon of an fluidic like ether, then is an effect, and not a fundamental force in itself (i.e., ala George Stokes). I know this is considered very unlikely now, but considering we have no theory explaining mechanistically what causes gravity (vs. being able to predict its effects locally, which we can do very well), we need to keep an open mind.
How do you manage to pack so much crank misconceptions in your posts?
?

I am talking fundamental physics/cosmology here. I am not talking about the ability to predict the effect of gravity, which is well founded (locally and up to at least some size larger than our solar system, but smaller than the Milky Way, unless you also want to add more metaphysics, i.e., dark matter, in which case, potentially much larger than the Milky Way).

68. Originally Posted by JoeSixPack
Originally Posted by xyzt

How do you manage to pack so much crank misconceptions in your posts?
?

I am talking fundamental physics/cosmology here.
No, you are just "packing" crank idea upon crank idea.

69. Originally Posted by MagiMaster
Originally Posted by JoeSixPack
Again, if it is universal, and "magic" (i.e., action at a distance or attractive)
I'll leave it to the people who are better versed in the details to, well, deal with the details, but I can comment on this. Spacetime curvature isn't magic action at a distance. When you put a bowling ball in the middle of a trampoline, the fabric takes time to settle into its new shape and then other objects on that trampoline will start rolling towards the bowling ball. Now, that's only a rough analogy, but changes in the curvature of spacetime (from the movement of mass for example) do take time to propagate. (As it happens, they propagate at the speed of light.)

Edit: Also, when you (and people like you) refer to a mechanical explanation, I really have no idea what you mean. Do you mean something like a universe built out of little springs and gears?
Interestingly, this rough analogy also implies a gravitational force pointing downwards on the trampolie. Otherwise the objects would not start rolling towards the bowling ball.

As to mechanical explanation, I am just looking for a physically viable explanation. For instance in chemistry we can describe a reaction as sharing of electrons between nuclei. And in addition, we have means to identify and validate to some reasonable degree of confidence the existence of elctrons and nuclei (and their components, etc.), as well as the ability to sense charge. Gravity as a physical theory is nowhere near this well understood (in fact I would say other than a few hypothesis such as involving the Higgs boson there really is no viable physical theory).

70. Originally Posted by xyzt
Originally Posted by JoeSixPack
Originally Posted by xyzt

How do you manage to pack so much crank misconceptions in your posts?
?

I am talking fundamental physics/cosmology here.
No, you are just "packing" crank idea upon crank idea.
crank theory = something that xyzt does not understand or agree with?

71. Originally Posted by JoeSixPack
(in fact I would say other than a few hypothesis such as involving the Higgs boson there really is no viable physical theory).
Your opinions are irrelevant. This is a classical example of crankiness : "I do not understand this theory, therefore it cannot be correct".
BTW, for your education, the Higgs boson is no longer a hypothesis. It was detected, In 2012. Get with the program.

72. Originally Posted by JoeSixPack
Originally Posted by MagiMaster
Originally Posted by JoeSixPack
Again, if it is universal, and "magic" (i.e., action at a distance or attractive)
I'll leave it to the people who are better versed in the details to, well, deal with the details, but I can comment on this. Spacetime curvature isn't magic action at a distance. When you put a bowling ball in the middle of a trampoline, the fabric takes time to settle into its new shape and then other objects on that trampoline will start rolling towards the bowling ball. Now, that's only a rough analogy, but changes in the curvature of spacetime (from the movement of mass for example) do take time to propagate. (As it happens, they propagate at the speed of light.)

Edit: Also, when you (and people like you) refer to a mechanical explanation, I really have no idea what you mean. Do you mean something like a universe built out of little springs and gears?
Interestingly, this rough analogy also implies a gravitational force pointing downwards on the trampolie. Otherwise the objects would not start rolling towards the bowling ball.

As to mechanical explanation, I am just looking for a physically viable explanation. For instance in chemistry we can describe a reaction as sharing of electrons between nuclei. And in addition, we have means to identify and validate to some reasonable degree of confidence the existence of elctrons and nuclei (and their components, etc.), as well as the ability to sense charge. Gravity as a physical theory is nowhere near this well understood (in fact I would say other than a few hypothesis such as involving the Higgs boson there really is no viable physical theory).
Besides xyzt's response, we can in fact measure curvature. See, in flat space, a triangle's angles always add up to exactly 180 degrees, but in curved space this is no longer true. (There are other ways of measuring the same thing.)

As for the trampoline, that is just one reason why it's only a rough analogy. But it also demonstrates that you somewhat missed the point. See, the trampoline would be analogous to a two-spatial-dimensions universe. If anything down would be forward in time (although that's really stretching the analogy a bit).

Also, none of that gets any closer to explaining what you mean by a mechanical explanation.

73. Also, none of that gets any closer to explaining what you mean by a mechanical explanation.
Infinitely stretchy invisible rubber band attached to everything.

74. Originally Posted by JoeSixPack
Curvature of spacetime is a mathematical concept, but ultimately needs to be translated into some physical mechanism.
Why do you need a steam-punk clockwork model of the universe?

As the geometry of space-time changes we experience a number of effects the most obvious of which appears as a force that we call gravity.

You have heard of geometry, I assume. The Greeks were very keen on it.

75. Originally Posted by JoeSixPack
As to mechanical explanation, I am just looking for a physically viable explanation.
We have a physically viable explanation. It works really well.

Gravity as a physical theory is nowhere near this well understood
By you.

(in fact I would say other than a few hypothesis such as involving the Higgs boson there really is no viable physical theory).
The Higgs boson has nothing to do with gravity (apart from being responsible for a tiny proportion of the mass of matter).

76. Originally Posted by JoeSixPack
Interestingly, this rough analogy also implies a gravitational force pointing downwards on the trampolie. Otherwise the objects would not start rolling towards the bowling ball.
Doh! The concept of an analogy is just sooo hard.

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