# Why two mass attracts each other?

Discussion in 'Physics & Math' started by hansda, Mar 19, 2013.

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1. ### Markus HankeRegistered Senior Member

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That is precisely my point. You don't see just space - you see the shooting star moving through a region of space in a period of time. Without time there would be no movement.
Remember that Farsight's assertion was that you see only space.

3. ### Markus HankeRegistered Senior Member

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Sorry, but that makes no sense whatsoever. The ruler is not fixed, it is just as arbitrary as a clock. You can measure time with a clock, but you can also measure it with, say, particle decays.
There is no difference whatsoever between the two when it comes to "models".

5. ### Markus HankeRegistered Senior Member

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Discard the clock then, and use particle decay instead, or atomic oscillations. It's direct observation, no clock mechanisms involved.
Motion is a change in position over a period of time.

Are you arguing that time somehow does not exist ?

7. ### Markus HankeRegistered Senior Member

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If they are self-correcting with a zero net effect, then you wouldn't get the results that GR does, because GR's predictions are certainly not "zero" effects. If Farsight himself acknowledges that permittivity and permeability must vary for his idea to work.

I never said that the space is different - what GR states is that the geometry of space-time varies, not the electromagnetic properties of space. They aren't the same things. The laws of electrodynamics cannot change, only the geometry of space-time does. That is what I meant when I said that light continues to propagate at exactly c, just the null geodesics it traces out have a different intrinsic geometry.

Yes, it is an elementary particle, as stated. In any case, the predictions of GR work for both elementary and composite particles. There are no differences.

I don't know what you are trying to say, but a particle's life span does not depend on total energy. You can produce a nearly stationary muon on earth, and produce a nearly stationary muon on the ISS ( both have same energy ), and you will find that the one on earth lives slightly longer by comparison. This is because of gravitational time dilation.

No offence taken. Bear in mind however that only because you cannot "make sense" of something does not mean that this something is wrong. There is no logic correlation.

Yes, indeed. Thus far however there is no experiment in existence which has ever detected light propagating at anything else but exactly c in vacuum, no matter what the gravitational environment is.

8. ### UndefinedBannedBanned

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1,695
That is not my naive understanding when I see a shooting star motion across space, because I do not automatically interpret that through some theory. I just see motion across space. If you choose to "time" its motion then that is up to you using another cyclic motion as a "clock" standard timing device. But whether you "time it" or not, the motion takes place and that is what "creates time" as a concept for you to put onto the shooting star motion, isn't it? You don't "see" time. Motion is the basis for the concept of time in any situation where timing is used by observers. If no observers to apply the concept of time or the use of clocks based on motion, then it is just motion across space which may be theoretically interpreted as some "time concept" after but not before motion exists.

When you say "there would be no movement without time", that is an theoretical "add on" to what is just happening. In my naive understanding it is the motion that exists as observable. The timing concept is based on that motion observable, and is used by human mind, not by nature. So time does not exist to "see". It is just something that is made possible as a theoretical construction used by humans to sequence and make sense "metrically" of any motion by comparing it to other "standards of motion" metrics. Time is a circuitous concept of human construct, but motion is what it is originally and observably. My naive understanding is that no "time" is necessary for motion, but motion is necessary for "timing standards" construct of us human and our theory "models".

Space exists and gravitational and other energy flux regions affect energy-particles including light moving through those regions. That is all I can naively deduce from seeing a shooting star. The "time" model concept with which you interpret and sequence and make sense of the motion across a distance of space region is only a modeling tool, not a necessary natural condition which motion depends on for it to occur naturally and not being "measured" or "timed" by anyone, yes?

My naive reading of Farsight is that he sees space and motion, not just space, when he sees a shooting star. So I think you might be misinterpreting what he said there. That may be what causes these emotional discussions between you on that point? It should be cleared up quickly or confusion will happen again and again I think.

Last edited: May 13, 2013
9. ### UndefinedBannedBanned

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Please see my previous reply to your other post about your statement that "time is necessary for movement". That covers my naive understanding that any motion used to "metricize" other motions is a clock standard of motion over space. The other point was that a "ruler" in the "rigid ruler" sense is able to be applied directly to the space or object surface/distance being measured. But a clock timing standard comparing motion standard with object motions is an indirect or logical application/comparison? If you get what I mean that is different between ruler and clock measuring processes?

I disagree respectfully with your last assertion here. In my naive understanding after naive observation, I naively conclude and say instead like this: "Motion is a change in position over a period of comparative motion I use as a clock ticking off a standard motion I use as a convention of timing for other motions across space." I can't naively justify anything more than that sort of conclusion, because no "time" existed before I made a "clock" out of some "conventionally agreed standard" of another motion, yes? What I call this theoretical modeling tool is not important. I can call it "fred", and it would still be a modeling tool/convention based on a motion across space compared with another motion across space, yes? Comparative motions are the observable physics, the timing is a secondary construction based on such motions comparisons according to agreed "metrics" of such standards. I can't see anything more than that naively.

Last edited: May 13, 2013
10. ### UndefinedBannedBanned

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1,695
I see what you are getting at. Thankyou for that insight. But when I spoke of self-correcting I meant when using light to make metrics for light in various conditions. Whether it is the the vacuum or the space (or whatever we call the environment of energy fluxing regions across which light travels), that is affected as Farsight says, I can't conclude yet because I still have more questions after some of the other misunderstandings get cleared up enough for my naive understandings to gel on that bit.

Yes I understood that from your previous posts. Does not the energy fluxing in a region of space contribute to that space's "conditioning" for all the other processes that happen across it? If so then space is more than just space-time, yes? It is space-energy and space-motion and all that sort of things observable. The space-time is a model as you say, but it assumes things that may not be as they are interpreted. Like I said to someone before, the "epicyclic model" of the planets and stars etc was a perfectly self-consistent model mathematically, but it wasn't close to what was really happening, was it? That is why my naive understandings demand me to ask what is behind all assumptions and conventions and such "modeling tool concepts" and the results from such models. Are they the last word for real things happening? I can't agree they are, yet.

I thought so. Thanks for confirmation. But just because we can't detect smaller components, it doesn't mean a particle or packet is "further indivisible". That is assumption I naively can't agree with yet. To me they all still are composite things until we know for sure some of them are not. Predictions are what models are for. But predictions can be made from "epicyclic models" too, the best way for me is to try and naively understand it all regardless of model predictions and results. I try to understand directly observables and logical consequences. Theories are useful, but not the last word for me, yet.

There is rest energy component, yes? There is energy component from particle speed in SR isn't it? There is energy component from gravitational potential or position, yes? So the faster a Muon the more energy the longer life, yes? Similarly we add to that SR speed component more energy influx from gravitational field which Muon speeding to ground keeps getting because it is moving through that field and not just sitting at one "level', yes? So my naive observation is that the Muon is speeding and its energy is being added to so its "speed only lifetime" is being extended by the "gravitational energy input" (not just speed increase due to short period of acceleration as such) as it ploughs through the field of gravitational energy. So yes, the energy of a particle affects its speed lifetime by affecting that process previously determined by its speed only component of energy. So the total energy would be more for a Muon ploughing through and gaining some gravity field energy to add to the particle's speed energy? So lifetime is different?

The "c" is calculated from frame dependent clock and distance factors, yes? So things get compensated for one way and the other so the "c" always pops out. But what is happening physically rather than mathematically calculated values where clocks and rulers change due to energy states and speeds and gravity energy fluxes and all sorts of other things that happen in "space" (not "space-time" because that would be circuitous to say the spacetime model uses light and clocks to make a model that tells us what clocks and light is supposed to be doing?).

Good. Yes of course. I am wrong when I am wrong. I understand this. But my naive understandings can sometimes help cut through the confusion and maybe in some things I am right? Until all the things have been settled and no more naive questions rise in my mind because all things are settled right, then we will know the right and the wrong for sure! Thank you and Farsight for discussing things, because it helps me come closer to knowing for sure where I may be wrong and where I may be right.

11. ### Markus HankeRegistered Senior Member

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So you are saying that there can be motion without time ?
How do you define the term "motion" ?

Your naive understanding is wrong on this point. Motion is defined as a change in position over time. It has been defined that way since Newton in the 1600s. Of course you are free to disagree, but then that would mean you are rejecting 400 years worth of classical physics even before GR, and we will no longer have a common frame of reference within which to continue this discussion in any meaningful way. There is limits to what we can reject without turning all of physics into a farce.

If there is no time, there is no motion in space. That has nothing to do with "abstract models", it is simple fact of the universe.

No, I understand him quite well. He does not claim that time does not physically exist, he just wants to separate it from space, as Newtonian physics does.

12. ### Markus HankeRegistered Senior Member

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To be honest, this is too garbled for me to give a meaningful reply. All I can say is that "energy flux" has no bearing on vacuum permittivity and permeability.
As for the latter part - I have made it clear already that GR is not the last word. Its domain of applicability is limited; it cannot handle any quantum effects, and there are even some classical effects that it cannot describe. So yes, there will be a more powerful model superseding it eventually; however, that is not the point at stake on this thread. Farsight does not dispute that GR gives correct results mathematically, he just disputes that it has anything to do with space-time curvature, quite contrary to current scientific consensus.

I am talking about gravitational time dilation, not coordinate time dilation. Both muons are at rest, the only physical difference between them is their relative position within the gravitational field. The muons are produced there and then, so there is no "speeding through fields" involved. I am, with this experiment, eliminating all physical differences except position.

That kind of argument again precludes the appearance of any kind of net effect. If between any two given points within a gravitational field exactly c always "pops out" due to "compensating" effects, then obviously the speed never has a net variation, so you get no effects such as the ones predicted by GR.

Btw, when you say "clocks and rulers change" as you did above, then that is pretty much exactly what GR states anyway. In GR clocks and ruler do change, because the geometry of space-time changes.

13. ### hansdaValued Senior Member

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2,424
In the case of "measuring distance", "distance" is compared with "distance".

In the case of "measuring time", "time" is not compared with "time" like in the case of "measuring distance". Here the principle of "simultaneity" is used to measure "time". To measure 'time interval' between two events, clock is also considered as a separate event. Problem with measuring "time" directly is that we can not see "time", the way we are able to see "distance". Though we can see the motion of a mass, hence we have an 'idea of time'.

Are you suggesting "time reversal" or "time dilation as if flow of time slows down, implying time-reversal"? See this paper.

"Time" is "model" because we cannot see 'time passing through a mass'. "Distance" is "not model", because we can see the size/dimensions(distance) of a mass. Though we can see 'movement of a mass' but we cannot see 'time passing through a moving mass'.

14. ### hansdaValued Senior Member

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'Bending of light in space' can also be explained with 'changing refractivity index(which depends on permittivity)'. See this paper.

15. ### Markus HankeRegistered Senior Member

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I don't know what you mean by that, but if you abandon the notion of separate "time" and "space", and just consider space-time instead, then the arc length between two events is just a simple distance. No confusion here.

No, I am merely suggesting that there are more ways to measure time than just mechanical clocks.

This has no meaning. We don't see "space" penetrating masses either - so what ?
Consider yourself at 4 years of age. Then consider yourself at 20 years of age. Are there differences ? Of course there are. Time has passed for you. Saying that time is not real just because you can't "see" it is a non-sequitur.

No, this is trivially wrong, and has long since been shown not to work. It's an old idea. For one thing, if you do the numbers you will find that for strong gravitational fields they do not match by a factor of two. Also, refraction is dependent on frequency, whereas gravitational light deflection is not. The models are in no way physically equivalent, and you will find the maths showing this in the article.
In fact, this is all mentioned and explained in the link you provided - did you actually read the text ? It would seem not, because otherwise you would not have made the statement I have quoted you on.

The fact that light refraction ( which is what a change in light speed is ) due to a changing vacuum permittivity is frequency dependent whereas gravitational light deflection due to space-time curvature is not, is also a major problem for Farsight's idea, since we do not observe any frequency dependence in gravitational lensing.

16. ### hansdaValued Senior Member

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You are going into 4D, mathematics and spacetime-model. All "observable things" happen in 3D. Reality is 3D. 4D is a model. Mathematics in 4D model for predicting 3D events is OK.

Whichever clock you consider, be it mechanical or atomic; it follows "simultaneity" principle. There is no direct measurement of time.

Can we not see the distance(space) of a rule? Can we not see the size of a mass? How much volume it is occupying in the space? May be we are not able to 'empty space'.

I am not denying idea of time but we dont have a direct perception of time like distance.

17. ### Markus HankeRegistered Senior Member

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So you are denying the existence of time, in other words.

You are contradicting yourself now. If you are not denying the existence of time, and you are not denying the existence of 3D space, then you must accept a 4D universe.
If you are denying time, then you cannot perceive yourself getting older ? What a strange world you live in !

So be clear - do or do you not accept that time exists ?

18. ### Beer w/StrawTranscendental Ignorance!Valued Senior Member

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Farsight is such a bewitching character -people like him actually exist! I guess being watchfully amused is probably the best way to learn of these non-fictitious beings.

Wonder if he also has super powers?

19. ### UndefinedBannedBanned

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1,695
My own naive understanding from observation goes something like two ways:

(1) Motion is defined by nature without human modeling techniques; but if we humans want to make some logical definition to match our naive observations we could say that

(2) Motion is a change of position of an object between instances of our observation of its instantaneous position in a sequence of instantaneous positions which we make sense of linearly as motion across space distance represented by summation of all instantaneous positions for the distance under study.

We use "clocks" (external ones for science and internal ones in our brain for our "sensing and predicting" patterns and behaviour) to compare such "apparent motion traces" across space of a study object's motion, and we call the comparative values a measure conventionally called "time" in our theoretical construct modeling that behaviour. The continuity of said sequence of instantaneous positions and comparisons are used by us to make a "moving picture" graph we can study piecemeal or as a dynamic visualization called a "video" either as simulation or direct movie photography techniques.

Naively I never "see" nature using "time" like we use in our models. That model and time is a device for analysis, not a natural phenomena in itself. I don't have a problem with what we call it, "time" will do just as well as "fred" would. The confusion comes to my naive understandings when "time" label for "motion comparisons" is treated as fundamental natural thing instead of just convenient name for the physical observables involved and the comparisons made between those observables we label "timing".

Nature does not "define time" in the way we do. That is the issue and confusion between what is natural observable and what is our "definition according to our brain/models". The model is not the natural observable, yes? I have no problem with us defining things, but when that defined thing is somehow made into a natural observable because of not realizing the difference between modeling and natural observable, then my naive mind rebels at my trying to convince it that "time exists" as we define it, rather than as nature produces it (by motions we can compare in our modeling processes and maths).

You say that again and again but it does not make it so naturally, only in our 4-D model of 3-D nature's motions (processes of change explained before above). Nature is based on motions of nature not on "time" of nature, because in my naive understandings nature itself does not even know "time" exists, only "motions".

Or are you claiming there is a "natural absolute universal time standard" which nature is "consulting" as it makes things move in space?

But isn't that alleged attempt at "separation" only in your mind/model? As far as I naively read Farsight so far, he just says that what is observable is 3-D space and that motions occur across that space as observables?

The rest seems like arguing from your (possible misinterpretation) putting more into his observation than he actually has said as far as I have read him on that here? Because all the models can retain "time" dimension as an abstraction of "motion comparisons observables" and not as an observable natural thing "time" in itself, then no changes to analytical models and theories are required at all, yes? As far as I read Farsight, he just wants to make the distinction between "time" as a tool and "abstract" dimension, and the "motion comparisons" which that abstract tool uses for its role in our models and theories, yes?

So I think maybe you two are arguing hotly because of some "perceived threat" which doesn't exist from either side of this "issue" which I think is really a "non issue" from my naive listening of what has been said between you on this. Sorry, but I really can't see your "issue" with each other on this, because I naively understand both sides and understand the distinctions and the role each plays in the science. One is the "irreducible observables" case (space and motion natural), and the other is the "useful abstractions" case (space and time model). Both are necessary to avoid confusion in my naive understandings of what it's about. Thankyou both for discussing it so much because it has helped me a lot.

Last edited: May 14, 2013
20. ### UndefinedBannedBanned

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Maybe I am not clear? The quantum vacuum properties determine what goes on in it, yes? The energy content in region of Quantum Vacuum determines the energy available for a process happening and it not happening, yes? So there is something fundamental below the "geometry only" modeling treatment of what is happening in "flat" or "curved" space regions containing Quantum Vacuum conditioned by all sorts of energy flux content above zero point energy content, yes? I understand what GR/SR are modeling as "geometry", what I naively do is try to look below that in Quantum Vacuum scale and try to think what is happening there which we superficially model in "geometry" terms. I have no problems with GR/SR, they are useful sure! But they do not satisfy my need for naively understanding more than the "geometry models" tell me about what happens really naturally not "abstractly geometrically", if you understand where I come from? Thankyou again for your discussion, it helps make clear some things which confused me and didn't know why until I read this discussion between you and Farsight. I will leave this discussion now and come back when I have thought through all that you and Farsight have discussed. Goodbye and thankyou, Markus Hanke, Farsight and przyk!

21. ### Write4UValued Senior Member

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I am not sure if the OP question was answered, but in case it is still open to input,

IMO, two massive objects, or three, or one hundred, do not attract or repel each other by potential differences, such as polarity. They always 'appear' to attract each other.

I see this as a (potential) function of spacetime itself, caused by the presence of a massive object. Each massive object creates a spacetime distortion, a kind of "dimple" in the fabric of space which allows other objects to fall into the "dimple", toward the massive object. Thus no matter how many massive objects there are, each creates it's own dimple in spacetime and together they make one giant dimple and all objects within reach fall toward the center of the largest dimples and ultimately to the center (the sum of mass) of all spacetime dimples. I think black holes are extreme examples of such spacetime distortions.

Perhaps this is an expression of Gravity, where the "center of gravity" is always at the center of the spacetime dimple, the most massive part of a massive system.

I am confident we can say "spacetime dimple" because, as I understand it, the passage of time itself is also affected in the proximity of a massive object. I don't see how the two can be separated and IMO, each tends to confirm the other, don't ask me how......

22. ### Markus HankeRegistered Senior Member

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I think it might be best to leave it at this for now. We have moved too far off a common ground; if you do not even acknowledge that motion has anything to do with time, then I don't really see how we could have a meaningful discussion about GR, which is what the thread was initially about.
One more thing - "naive understandings" are not always good reference points against which to evaluate the merits of a theory, especially not when it comes to relativity. That just as an aside.

23. ### PhysBangValued Senior Member

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2,422
I believe that Farsight's delusion around this particular point is based, like many, on the fact that he really has never studied physics. He only does a textual analysis of abstracts and the introductory sections of Einstein's chapters. He really has no idea of how a physics observation, experiment, or explanation is carried out.

Notice how he never answers when asked how his waggling his fingers is evidence for movement. I suspect that he once tried and realized that he couldn't do it without invoking time and so, dishonestly, he stopped trying to answer the question.