[RazaTD]

The Variations in Gravity are the supposed variations to gravity due to either the variations in strength of the gravitational field of the earth or due to the presence of masses such as hills or celestial bodies. It is often stated that the strength of gravity decreases with altitude or that the gravity of the Sun and Moon pulls upon the earth's surface.

The FE model of Celestial Gravitation postulates that the celestial bodies have a slight gravitational pull, which accounts for tidal effects and the lessening of g with altitude. Other FE models question whether variations in gravity actually exist at all. The few effects suggesting variations are questionable, contradicted, and may be attributed to other causes.

Gravity generally appears to behave as if the earth is accelerating upwards, that the strength of gravity is uniform, and there are no other gravitating sources around us.

This comes from the wiki. There are a lot of problems with this. First of all, it is a known fact that gravitational acceleration is NOT constant. FE must provide some mechanism to explain that variation. This requirement means those FE models that deny this variation are false.

The models that do not deny this variation attribute it to gravity but a special version. This is a celestial gravitation model where only the sun and the moon can produce an attractive force.

This is EXTREMELY easy to debunk. If the celestial bodies exert force and nothing else does, then we just need to look at how gravitational acceleration varies over the surface of the Earth. It turns out that there is a lot more going on than just the sun’s and the moon’s gravity.

However, let’s assume that a superior FE model states that the general gravitational acceleration is the result of UA and the local variances is actually the result of gravity that exists between everything just like in the RE mode except it’s much weaker. However, the challenge is to prove that the force of gravity is much weaker than the RE value.

The wiki is broken 😎

[scomato]

The fact that gravimeters read a stronger downward pull (by a needle and a spring sensitive to 0.001 G's) at the top of a mountain (where there is most mass underneath) and low gravity at inverse locations on the Earth, should be compelling evidence that the Earth's mass is responsible for its own local gravity.

There's also the fact that mining companies use this method to detect karsts and voids beneath the surface, where they may contain natural gas and oil. Gravimetric prospecting is very effective, and provides very accurate readings of things such as salt domes. People have been using this method for decades, below are some diagrams from work published in 1944. Just to demonstrate how accurate their readings were, despite only having access to very simple instruments.



This second diagram shows calculations based on their gravimeter analysis with the observed cross section of the salt dome. Given that the real profile of the dome was not known prior to the prediction, and the prediction was very accurate. Not perfect, but very good.



Citation
Barton, Donald C.. "Case Histories and Quantitative Calculations in Gravimetric Prospecting." Pet. Technol. 7 (1944): 1–49. doi: https://doi.org/10.2118/944111-G

We must conclude that the mass of the Earth beneath our feet is responsible for the downward force that keeps us from floating in zero G.

It's a very simple model, more mass/greater density = more gravity. It is easily testable, measurable, predictable, and is applied in real life to make a lot of people a lot of money for a very long time.

If Celestial Bodies were responsible for gravitational anomalies, then the fact that gravimetric analysis finds what it expects to find (ie. in the above, an accurate profile of the Nash Salt Dome) it would have to be attributed to coincidence! Furthermore, gravimetric analysis should not be repeatable, if their results were coincidence or attributed to celestial objects (given that they are moving relative to our position).

[Tom Bishop]

The fact that gravimeters read a stronger downward pull (by a needle and a spring sensitive to 0.001 G's) at the top of a mountain (where there is most mass underneath) and low gravity at inverse locations on the Earth, should be compelling evidence that the Earth's mass is responsible for its own local gravity.

...

It's a very simple model, more mass/greater density = more gravity. It is easily testable, measurable, predictable, and is applied in real life to make a lot of people a lot of money for a very long time.

That's not true at all. The gravity anomalies are negative on the mountains, not positive.

https://wiki.tfes.org/Isostasy

http://earthsci.org/education/teacher/basicgeol/earthq/earthq.html

“ Negative anomalies exist beneath mountain ranges, and mirror the topography and crustal thickness as determined by seismic studies. Thus, the low density continents appear to be floating on higher density mantle. ”

Also, gravimeters aren't reliable to determine what is buried underground:

https://wiki.tfes.org/Gravimetry

Underground Target Detection

While gravimetry results have a relationship with geographical areas relating to positive anomalies at the seismic zones and negative anomalies on the continents and mountains, the use of gravimetry for reliable detection of underground targets is murkier. Gravimetry must be used alongside other techniques, as gravimetry alone provides poor understanding of the earth.

From a Los Alamos National Laboratory associated geophysics program -
https://permalink.lanl.gov/object/tr?what=info:lanl-repo/lareport/LA-UR-17-30673 (Archive)

  “ Both negative and positive density contrasts can be modeled for any gravity survey target. The lower panel shows a cross-section through the ground. The circles represent denser (right) and less dense (left) regions. The upper panel shows the gravity that might be measured at the surface. ”



  “ WARNING!
Gravity is a Potential Method, meaning that we try to interpret the sources that contribute to a total potential force (this is also true for magnetic surveying). As such, we can always find a variety of physical models that can produce the same observations. This means that no model based solely on gravity observations can be considered to be uniquely correct. Always, additional information is needed before confident interpretation of the gravitational data is possible.
~
Combining gravity models with other information – geologic, seismic, electromagnetic, will improve confidence in the results. Gravity is a potential method, meaning that its results are ambiguous in isolation. Other information is always needed to interpret gravity anomalies with confidence. ”

From An Introduction to Geophysical Exploration -
http://www.science.earthjay.com/instruction/HSU/2016_spring/GEOL_460/lectures/lecture_07/geophysical_expoloration_gravity.pdf (Archive)

  “ The interpretation of potential field anomalies (gravity, magnetic and electrical) is inherently ambiguous. The ambiguity arises because any given anomaly could because by an infinite number of possible sources. For example, concentric spheres of constant mass but differing density and radius would all produce the same anomaly, since their mass acts as though located at the centre of the sphere. This ambiguity represents the inverse problem of potential field interpretation, which states that, although the anomaly of a given body may be calculated uniquely, there are an infinite number of bodies that could give rise to any specified anomaly. ”

From a Doctoral Thesis, Gravimetry for Geothermal Exploration -
https://doc.rero.ch/record/255651/files/00002456.pdf (Archive)

Gravity anomaly interpretation

  “ Interpretation of gravity anomalies can be made in two ways, directly or by building a gravity model. Concerning the latter, the gravity anomaly generated by the model will be compared with the measured gravity. In all cases the nature of the gravity makes its interpretation ambiguous, as several different bodies can induce the same anomaly as presented in figure 2.16. Therefore gravity is often used in combination with other geophysical methods to avoid or decrease the ambiguity. ”

From a course, Physics in Proportion -
https://www.mtholyoke.edu/courses/mpeterso/phys103/PhysicsInProportionI.pdf (Archive)

  “ A gravimeter is like a crude eye, looking into the Earth, but without any ability to focus, able to report only that there is something interesting nearby or there isn’t. ”

[stack]

Also, gravimeters aren't reliable to determine what is underground:

I don't get it. All of your citations ultimately say the same thing as summarized in the presentation you provided here,
https://permalink.lanl.gov/object/tr?what=info:lanl-repo/lareport/LA-UR-17-30673 (Archive):

 Summary:
• We can measure changes in gravity from place to place on the earth.
• These measurements require careful recording of location, elevation and time for   each   reading.
• These readings must be adjusted for   known effects (such as elevation, latitude, tides) that can bias our   data and mask the signal of interest.
• After making corrections to our   data,   we can remove regional trends to obtain local Bouguer anomalies.
• The Bouguer anomalies arise from variations in the subsurface density structure.
• We   can build models to explain   our observations, but   these models must be consistent    with   what   is known about the local geology.
• Combining gravity models with   other information– geologic, seismic, electromagnetic, will improve confidence in the results.

See this bit: "We can measure changes in gravity from place to place on the earth." Isn't your whole thing that we can't?

All the papers, articles, presentations you cite say you can measure changes in gravity - You just have to be very meticulous and thorough in doing so, taking in a multitude of factors to get to a high confidence of your findings.

Why are you citing papers that say you can measure gravity differences when you claim you can't?

[Pete Svarrior]

If the celestial bodies exert force and nothing else does

I don't think anyone here is making that claim, and you did not source it from the Wiki. The Wiki is not broken, merely your imagination of FET.

I really wish you guys wouldn't try to get us to defend such blatant strawmen. It rarely works.

[RazaTD]

If the celestial bodies exert force and nothing else does

I don't think anyone here is making that claim, and you did not source it from the Wiki. The Wiki is not broken, merely your imagination of FET.

I really wish you guys wouldn't try to get us to defend such blatant strawmen. It rarely works.

I also addressed the case where everything attracts.

[Pete Svarrior]

I also addressed the case where everything attracts.

No, you didn't. You presented a "challenge" of "if the Earth is round then how can it be flat?":

However, the challenge is to prove that the force of gravity is much weaker than the RE value.

Once again, I'd appreciate it if you didn't waste our time with such bad faith arguments. It won't work. We will not presume the correctness in RET while debating FET, for reasons that hopefully don't need to be spelled out.

[fortytwo]

If the celestial bodies exert force and nothing else does

I don't think anyone here is making that claim, and you did not source it from the Wiki. The Wiki is not broken, merely your imagination of FET.

I really wish you guys wouldn't try to get us to defend such blatant strawmen. It rarely works.

Sometimes I really get lost here ...
IMHO the "strawman" is clearly one of the options which are offered in the FET wiki

https://wiki.tfes.org/Universal_Acceleration

Q: Why does gravity vary with altitude?

A: According to the model of Celestial Gravitation the Moon and Stars have a slight gravitational pull. This is given as an answer to tidal effects and variations of gravity with altitude. Other models reject the concept of gravity entirely and question whether those slight variations in gravity actually exist. See: Variations in Gravity

https://wiki.tfes.org/Variations_in_Gravity

The FE model of Celestial Gravitation postulates that the celestial bodies have a slight gravitational pull, which accounts for tidal effects and the lessening of g with altitude. Other FE models question whether variations in gravity actually exist at all. The few effects suggesting variations are questionable, contradicted, and may be attributed to other causes.

And as quoted in the OP:
https://wiki.tfes.org/Celestial_Gravitation

So, if "and nothing else does" is not true, what else does?

[Pete Svarrior]

Ah, the quote-cherry-pickers are out in force today, I see.

I will ask, politely, one last time: if you haven't figured out FET yet, don't come here and try to explain to us what it is. Learn the subject you're trying to disagree with prior to disagreeing with it. Even better - learn the subject prior to deciding that you want to disagree!

A little hint for you: RazaTD's strawman was rooted in assuming that the Earth is not a celestial body. This is his original proposition, distinct from anything you'll find in the Wiki. Context is crucial.

[AATW]

I will ask, politely, one last time: if you haven't figured out FET yet, don't come here and try to explain to us what it is. Learn the subject you're trying to disagree with prior to disagreeing with it. Even better - learn the subject prior to deciding that you want to disagree!

This is fair, although in this case there's not much to go on. The Wiki page on this subject basically just says "some people think this is a thing". But then the Wiki also says

Gravity generally appears to behave as if the earth is accelerating upwards, that the strength of gravity is uniform, and there are no other gravitating sources around us.

Which is demonstrably false and a contradiction to Celestial Gravitation. And if Celestial Gravitation is a thing then is the hypothesis that this force is one way? Otherwise surely the things would fall on us if things on earth were pulling on the celestial objects. Do the variations we can measure in gravity tally with the position movement of the celestial objects?

This whole area feels very poorly defined. Maybe because it is, I guess if it's a work in progress then that's fair enough. But you have one Wiki page which says:

"Celestial Gravitation accounts for tides and other gravimetric anomalies across the Earth's plane."

and another which says that the strength of gravity is uniform

[fortytwo]

A little hint for you: RazaTD's strawman was rooted in assuming that the Earth is not a celestial body. This is his original proposition, distinct from anything you'll find in the Wiki. Context is crucial.

I must admit, I made the same assumption and this assumption is based on reading the Wiki - how else could I learn FET?

https://wiki.tfes.org/The_Cosmos

It is sometimes asked that if the celestial bodies are spheres, why isn't the Earth a sphere? The logic that the Earth must be a sphere because the celestial bodies are spheres is only one possible interpretation.

Maybe you can lead me to the section in the Wiki, where it is stated that earth is also a celestial body in FET.

[SteelyBob]

Ah, the quote-cherry-pickers are out in force today, I see.

I will ask, politely, one last time: if you haven't figured out FET yet, don't come here and try to explain to us what it is. Learn the subject you're trying to disagree with prior to disagreeing with it. Even better - learn the subject prior to deciding that you want to disagree!

A little hint for you: RazaTD's strawman was rooted in assuming that the Earth is not a celestial body. This is his original proposition, distinct from anything you'll find in the Wiki. Context is crucial.

AATW is spot on Pete. You can't simultaneously demand that people 'learn FET' when the tool you present is vague and contradictory. The wiki says that gravity is uniform across the earth, and also that tides are caused by celestial bodies exerting gravity forces - both cannot be true. It does seem very much like you and Tom prefer not to back a horse, so to speak, because you know that both are flawed arguments and it is convenient to avoid committing to one.

[RazaTD]

RazaTD's strawman was rooted in assuming that the Earth is not a celestial body. This is his original proposition, distinct from anything you'll find in the Wiki. Context is crucial.

So what doesn't have gravitational acceleration then? Since FE can't say much about the nature of the Sun and the Moon and being able to directly test them is not accessible to laymen and FEers don't trust NASA and their robots, they could assert that such celestial bodies are special for whatever reason. But Earth is right here and easily testable. If Earth exerts gravity, what property does it have that other matter doesn't which makes this possible? Are there special rocks deep down that work like magnets but for gravity?

Obviously, you don't want to end up with all matter exerting gravity otherwise it's not celestial anymore, and why even have UA then? This will basically be RE gravity which FEer make fun of.

However, the challenge is to prove that the force of gravity is much weaker than the RE value.

Once again, I'd appreciate it if you didn't waste our time with such bad faith arguments. It won't work. We will not presume the correctness in RET while debating FET, for reasons that hopefully don't need to be spelled out.

This is not a bad faith argument. I am not asking you to presume the correctness of RE model. I proposed a model that is similar (possibly not because you haven't clarified whether matter also exerts gravity) to the one you just suggested where even Earth exerts gravity. Now by logical necessity, this gravitational force must be less than that on RE model because UA also contributes to the overall gravitational acceleration on the FE.

Acceleration on RE = 9.81 (approx.)
Acceleration on FE = A (exact due to UA) + B (celestial gravitation)

A must be significantly larger than B because as A approaches 0, celestial gravitation basically becomes a different name for RE gravity.
A must also be strictly vertical while B is like a point source.

So, the task for FEer, only if they concede that matter exerts gravity (which you are just a few steps away from as you have just conceded that Earth has gravity), is to demonstrate that B is significantly less than 9.81, which is what RE claims is the gravitational acceleration.

I don't see where I have presumed the correctness of RE here. The value of gravitational acceleration 9.81 is what we observe. Making the assumption that it must be the same on Flat Earth does not mean I have assumed RE is correct. 9.81 is an observation that both models must derive.

[Pete Svarrior]

Maybe you can lead me to the section in the Wiki, where it is stated that earth is also a celestial body in FET.

I suspect that's not stated anywhere. I also suspect that the word "chair" has not been defined in the Wiki. We have to rely on our readers' basic literacy skills to some extent.

You can't simultaneously demand that people 'learn FET' when the tool you present is vague and contradictory.

Why? If you don't like our resources (whose purpose is largely not to teach you a model - if you're misusing it, I can't really help you with that), you can use other FE literature. Imagine I used that argument against you - no, I won't look up whatever you'd like to explain to me, because you haven't yet personally written a comprehensive whitepaper on it yourself. It's a ridiculous standard that you'd never allow to be applied to you, and rightly so. Now you simply need to extend that courtesy to people whose views you dislike.

So what doesn't have gravitational acceleration then?

I repeat my request: please learn FET BEFORE posting here.

This will basically be RE gravity which FEer make fun of.

I am not asking you to presume the correctness of RE model.

You are, by presenting a one-sided "challenge" to prove your preferred model to be incorrect. I asked you not to waste our time, but you chose to double down. You're going to have to start fixing some of the gaping holes in your arguments if you want this conversation to progress.

[RazaTD]

Do you agree with this?

Acceleration on RE = 9.81 (approx.)
Acceleration on FE = A (exact due to UA) + B (celestial gravitation)

A must be significantly larger than B because as A approaches 0, celestial gravitation basically becomes a different name for RE gravity.
A must also be strictly vertical while B is like a point source.

[Pete Svarrior]

Do you agree with this?

I do not - there is very little in what you said that isn't horrendously wrong, both for RET and FET. Are you planning on filling your gaps in knowledge prior to posting here, as requested, or do you intend to continue wasting everyone's time with your nonsense?

[RazaTD]

Do you agree with this?

I do not - there is very little in what you said that isn't horrendously wrong, both for RET and FET. Are you planning on filling your gaps in knowledge prior to posting here, as requested, or do you intend to continue wasting everyone's time with your nonsense?

I read the wiki and apparently some FE models are UA so those are obviously wrong (can not account for local variances). Other FE models are celestial gravitation.

I think where I am getting wrong here is that UA and celestial gravitation do not mix?

If that’s so then let me address just celestial gravitation. I did not find the following information about the celestial gravitation:

If only celestial bodies exert gravity such as sun, moon, and earth, then what property of those bodies is it that allow this? Also what part of Earth exerts gravity? If I pick up a rock does it still exert gravity?

Sorry I can’t find this information anywhere on the wiki and outside the wiki.

[Pete Svarrior]

I see. I guess this thread has come to an end, then. We cannot meaningfully discuss your disagreements to positions nobody holds (strawman attacks), and you are openly unwilling to fix your arguments.

[RazaTD]

I see. I guess this thread has come to an end, then. We cannot meaningfully discuss your disagreements to positions nobody holds (strawman attacks), and you are openly unwilling to fix your arguments.

I can’t find information?

[Pete Svarrior]

I can’t find information?

Apparently so.

Locked.