Geocentricism, the Length of the Day, and a Non-Rigid Earth

Ladies and Gentlemen,

trth_skr on another thread about Gary Hoge has introduced me to the concept of geocentricism, which is the theory that the earth is fixed in space and the universe revolves around it. The Coriolis and centripetal accelerations seen that most scientists ascribe to the earth’s rotation are explained by geocentricism as the influence of these distant revolving astronomical bodies.

One possible weakness of the geocentric theory is that the earth’s motion is not uniform. Certainly it rotates on its axis through an angle of 360 degrees every 23 hours, 56 minutes, 4.09 seconds (more or less) on average–this is called a siderial day–but the complete motion of the earth (or of the universe around the earth) is more complex than this. Besides the supposed revolutions about the earth/moon barycenter and the sun (really the earth/sun barycenter), which I am sure the geocentricists have explained, there are the precession and nutation motions of the earth. There is also something called the Chandler Wobble. The geocentric theory needs to explain what would cause the universe’s motion to change in this way.

A second weakness of geocentricism is the question of what constitutes the earth. The earth is not a rigid body, solid though it may seem. It deforms on a daily basis–I mean the solid rock deforms–due to the tidal influence of the moon. Earthquakes set the entire globe to vibrating. Volcanic eruptions and erosion redistribute material across the surface. Tectonic plates slide across the top of the mantle, are added to at spreading boundaries, and slide down into the mantle at subduction zones. All of these phenomena have been observed directly; they are not theories. So I ask: what part of the earth forms the stationary basis that the universe revolves around?

  • Liberian

[quote=Liberian]One possible weakness of the geocentric theory is that the earth’s motion is not uniform. . . .
[/quote]

I’m sorry, but that’s ind of like referring to a possible weakness of the phlogiston theory of combustion.

<< So I ask: what part of the earth forms the stationary basis that the universe revolves around? >>

The central core, deep inside the heart of the earth, where Atlantis resides.

Please not another geocentrism thread, I can’t handle more than 1 a week. :whacky:

[quote=Liberian] So I ask: what part of the earth forms the stationary basis that the universe revolves around?

  • Liberian
    [/quote]

The center of mass.

let me say this–i ave really started , justthis past week, to really look into the geocentrism heliocentrim arguments–i must admit it has given me a headache–(very technical scientific arguments) and most people, who i have talked to about this (geocentrism) look at me like i am nuts (not that that matters) --but i will say this, wouldnt it be great if the geocentrists were right-that creation was literal (Genesis account) and that the other Biblical passages in the psalms and Job and 2nd chronicles were meant to be taken literally–and it would also sow that the earth is the center of God’s creation and would additionally sea volumes for his love of man on this earth–

Originally Posted by Liberian
* So I ask: what part of the earth forms the stationary basis that the universe revolves around?

  • Liberian*

[quote=trth_skr]The center of mass.
[/quote]

trth_skr,

Sorry but I need two more points. One point (the center of mass, you say) defines a position; the second point defines the x-axis of the coordinate system; the third point defines the y-axis of the coordinate system. The direction of the z-axis is taken as the cross product of the unit vectors in the x- and y-durections.

Another weakness is that what constitutes “the earth” is also changing. Hydrogen atoms at the top of the atmosphere leave the earth and leak off into space; meteoroids enter the earth’s atmosphere as meteors and sometimes land as meteorites, adding to what constitutes “the earth.” Since the space age started, spacecraft have also left the earth. How do you define the set of atoms whose center of mass is to be considered fixed?

  • Liberian

trth_skr,

Sorry but I need two more points. One point (the center of mass, you say) defines a position; the second point defines the x-axis of the coordinate system; the third point defines the y-axis of the coordinate system. The direction of the z-axis is taken as the cross product of the unit vectors in the x- and y-durections.

Another weakness is that what constitutes “the earth” is also changing. Hydrogen atoms at the top of the atmosphere leave the earth and leak off into space; meteoroids enter the earth’s atmosphere as meteors and sometimes land as meteorites, adding to what constitutes “the earth.” Since the space age started, spacecraft have also left the earth. How do you define the set of atoms whose center of mass is to be considered fixed?

  • Liberian

I guess I do not see the issue here. The physics in the Geocentric system are the same as any other system. What difference does it mean if there are minute changes to the mass of the earth?

[quote=trth_skr]I guess I do not see the issue here. The physics in the Geocentric system are the same as any other system. What difference does it mean if there are minute changes to the mass of the earth?
[/quote]

I may be a little confused as to what geocentricism is actually saying. I believe that it says that the earth is stationary. If that is accurate, then my concerns hold; if not, then I need correction.

For a body in three dimensions to be called stationary, three points on that body need to be fixed. If there is only one stationary point, the body is free to rotate in three dimensions. If two points are specified to be stationary, they define an axis and the body may rotate about that axis. To fix the position and orientation of the body, you need to specify three stationary points. You specified the first point as the center of mass of the earth. I am asking for the definitions of the other two points.

The problem with the earth not being constant through time is not so much one of mass as of momentum. When a meteorite hits the earth, the momentum of that meteorite is added to the earth’s momentum and, if the earth was not moving beforehand, the earth starts moving. A meteorite a mile across hitting with a speed of 7 miles per second (and most, if not all, meteorites are moving faster than that when they hit the earth) packs enough momentum to start the earth moving at a speed of about a foot or two per year. Smaller meteorites have a smaller effect, but it is still nonzero. So my question is: given that a meteorite has hit the earth, was the earth moving before the impact or was it moving after the impact? And since more than one meteorite has hit the earth, the question is multiplied.

  • Liberian

[quote=Liberian]I may be a little confused as to what geocentricism is actually saying. I believe that it says that the earth is stationary. If that is accurate, then my concerns hold; if not, then I need correction.

For a body in three dimensions to be called stationary, three points on that body need to be fixed. If there is only one stationary point, the body is free to rotate in three dimensions. If two points are specified to be stationary, they define an axis and the body may rotate about that axis. To fix the position and orientation of the body, you need to specify three stationary points. You specified the first point as the center of mass of the earth. I am asking for the definitions of the other two points.

The problem with the earth not being constant through time is not so much one of mass as of momentum. When a meteorite hits the earth, the momentum of that meteorite is added to the earth’s momentum and, if the earth was not moving beforehand, the earth starts moving. A meteorite a mile across hitting with a speed of 7 miles per second (and most, if not all, meteorites are moving faster than that when they hit the earth) packs enough momentum to start the earth moving at a speed of about a foot or two per year. Smaller meteorites have a smaller effect, but it is still nonzero. So my question is: given that a meteorite has hit the earth, was the earth moving before the impact or was it moving after the impact? And since more than one meteorite has hit the earth, the question is multiplied.

  • Liberian
    [/quote]

When a meteorite a mile across hits the earth, it causes the universe to move at the speed of a foot or two per year with respect to the fixed earth. If it hits off centre it changes the angular velocity (vector: amplitude and direction) of the rotation of the universe around the earth.

I’m surprised you didn’t think of that.

Alec
evolutionpages.com

[quote=hecd2]When a meteorite a mile across hits the earth, it causes the universe to move at the speed of a foot or two per year with respect to the fixed earth. If it hits off centre it changes the angular velocity (vector: amplitude and direction) of the rotation of the universe around the earth.

I’m surprised you didn’t think of that.

Alec
evolutionpages.com
[/quote]

Alec,

Sorry, I’m drifting a bit. Let me try to regain my bearings.

My second objection in this thread to geocentricism–the theory that the earth is stationary–is that the earth is not a rigid body, that one part of it moves relative to another part of it. I asked trth_skr what part of it is stationary, and he replied that it is the center of mass. I have two problems with this reply:

(1) To define a stationary coordinate system, you need three points. One of these would be the earth’s center of mass; the other two are not defined–at least not that I know of; trth_skr hasn’t answered me yet.

(2) The center of mass is defined as the average of the positions of a large number of atoms, weighted by the mass of each atom. How do we define the set of atoms to be included in this average? Before a meteor hits the earth, it is obviously not part of the earth and should not be included. After it hits the earth, it is part of the earth and should be included. At what point do we make the changeover and include the material from the meteor in the center of mass calculation? What non-arbitrary criterion do we use?

I apologize for the mention of the momentum. It appears at the moment to be a red herring, although the question of how the impact of a meteor locally on the surface of the earth can instantaneously affect the velocity of galaxies billions of lightyears away remains to be settled.

  • Liberian

[quote=Liberian]Alec,

Sorry, I’m drifting a bit. Let me try to regain my bearings.

My second objection in this thread to geocentricism–the theory that the earth is stationary–is that the earth is not a rigid body, that one part of it moves relative to another part of it. I asked trth_skr what part of it is stationary, and he replied that it is the center of mass. I have two problems with this reply:

(1) To define a stationary coordinate system, you need three points. One of these would be the earth’s center of mass; the other two are not defined–at least not that I know of; trth_skr hasn’t answered me yet.

(2) The center of mass is defined as the average of the positions of a large number of atoms, weighted by the mass of each atom. How do we define the set of atoms to be included in this average? Before a meteor hits the earth, it is obviously not part of the earth and should not be included. After it hits the earth, it is part of the earth and should be included. At what point do we make the changeover and include the material from the meteor in the center of mass calculation? What non-arbitrary criterion do we use?

I apologize for the mention of the momentum. It appears at the moment to be a red herring, although the question of how the impact of a meteor locally on the surface of the earth can instantaneously affect the velocity of galaxies billions of lightyears away remains to be settled.

  • Liberian
    [/quote]

I am with you 100%. I was being facetious.

Alec

[quote=hecd2]I am with you 100%. I was being facetious.

Alec
[/quote]

Alec,

Thanks for the clarification. I am engaged in the exceedingly difficult task of trying to prove a scientific theory wrong. Most theories are never disproven; simply everybody who believes them either dies or retires and nobody new replaces them. (There was a very good article on N-rays in Scientific American several years ago that concluded with that statement.) As such, since I am trying for proof or disproof, I need to have all my ducks in a completely straight row.

The ball is now in trth_skr’s court.

  • Liberian

[quote=Liberian]Alec,

Sorry, I’m drifting a bit. Let me try to regain my bearings.

My second objection in this thread to geocentricism–the theory that the earth is stationary–is that the earth is not a rigid body, that one part of it moves relative to another part of it. I asked trth_skr what part of it is stationary, and he replied that it is the center of mass. I have two problems with this reply:

(1) To define a stationary coordinate system, you need three points. One of these would be the earth’s center of mass; the other two are not defined–at least not that I know of; trth_skr hasn’t answered me yet.

(2) The center of mass is defined as the average of the positions of a large number of atoms, weighted by the mass of each atom. How do we define the set of atoms to be included in this average? Before a meteor hits the earth, it is obviously not part of the earth and should not be included. After it hits the earth, it is part of the earth and should be included. At what point do we make the changeover and include the material from the meteor in the center of mass calculation? What non-arbitrary criterion do we use?

I apologize for the mention of the momentum. It appears at the moment to be a red herring, although the question of how the impact of a meteor locally on the surface of the earth can instantaneously affect the velocity of galaxies billions of lightyears away remains to be settled.

  • Liberian
    [/quote]

Liberian:

I will try and answer your questions. I will use this post.

(1) No, you need three axis. Any time we create a coordinate system, this is somewhat artificial. There is a difference between making a coordinate system transformation and doing a calculation (i.e., on the geosynchronous satellites), say using general relativity and actually having a detailed physical model of the system. In the case of my assertion about geosynchronous satellites, this is simply a coordinate transformation. I would suspect that the best approach would be to constrain the average center of mass of the earth in 3 translational directions, as well as constrain the rotational motions, all to zero. The calulation, if properly done, will calculate the necassary reaction forces within the earth to maintain that constraint.

(2) In the case of a detailed model, you may want to account for mass changes, etc. In that case, I would think a good approach would be to choose a zero time, calculate the center of mass at zero, then as time advances, uipdate the center of mass. Of course this would be extremely complicated, but in principle, not impossible.

Now the model would also have to account for the effect of changing center of mass. This is where modelling the earth as gyroscopically stabilized (per MWT) comes in. As long as the center of mass does not change too much from its intital position, the gyroscopic stabilization should keep it stable.

A huge asteroid hitting the earth will cause a huge earthquake, made up of some fraction of the energy of the asteroid impact, plus some fraction of the change in position of the center of mass of the earth. Due to Mach’s principle, the rest of the universe will absorb some of the energies. I suspect the earth will absorb a fair amount of the direct impact energy, but the universe can change configuration ever so slightly to absorb any change in the center of mass, but this is a guess.

Keep in mind that in a rotating/translating earth frame, an impact will change the velocity of the earth’s translation (and possibly apply a torque cahnging angular velocity). In a fixed earth frame, it will change the precession dynamics and possibly the rotation velocity. Keeping in mind the infintessimal mass of the earth, relative to the universe, the change would be almost unobservable.

[quote=trth_skr]Liberian:

I will try and answer your questions. I will use this post.

(1) No, you need three axis. Any time we create a coordinate system, this is somewhat artificial. … I would suspect that the best approach would be to constrain the average center of mass of the earth in 3 translational directions, as well as constrain the rotational motions, all to zero. The calulation, if properly done, will calculate the necassary reaction forces within the earth to maintain that constraint.
[/quote]

I think we are saying the same thing in different ways. I say we need three points to define a coordinate system; you say we need three axes. I use my points to define your axes; I believe the end result is the same. My first point is the origin of the coordinate system. My second point is a point along the x-axis, thus defining your first axis. (Incidentally, the distance between the first and the second point must be constant through time for Geocentricism; otherwise the earth is moving in that its size is increasing or decreasing.) My third point is a point along the y-axis, thus defining your second axis. (Again, the distances between the third point and the first and second points must be constant through time for Geocentricism; otherwise your basic stationary reference is actually moving.) Your third axis is defined as perpendicular to the first two axes and fulfilling the right-hand rule.

If you have a way of defining a three-dimensional coordinate system that does not involve specifying three points I would be delighted to hear it. I don’t just mean “well, here are these three axes.” I need a way to specify the coordinates of any point on the earth in these three axes.

You mention constraining the position of the “average center of mass” of the earth to zero in three translational directions; this provides the first point, as (I think) we agreed earlier. I will get back to the question of what constitutes the “average center of mass” in a bit. The present problem comes with restraining the rotational motions to zero. Restraining the rotational motions of what? The earth is not rigid and if you restrain one part of it to be non-rotating then other parts of it will be rotating. They won’t rotate very far, and they will go back and forth, but an individual piece of the earth will have a nonzero instantaneous angular velocity. The reason I am trying to define the earth-centered coordinate system with my three points or your three axes is so that we will have something specific that is not rotating. By glossing over the process of constraining the earth to be non-rotating you are ignoring the difficulty completely.

(2) In the case of a detailed model, you may want to account for mass changes, etc. In that case, I would think a good approach would be to choose a zero time, calculate the center of mass at zero, then as time advances, uipdate the center of mass. Of course this would be extremely complicated, but in principle, not impossible.

This is an excellent idea, and leads one straight down the road towards Copernican theory. If the position of the center of mass is going to change with time, then the earth is no longer stationary.


Keep in mind that in a rotating/translating earth frame, an impact will change the velocity of the earth’s translation (and possibly apply a torque cahnging angular velocity). In a fixed earth frame, it will change the precession dynamics and possibly the rotation velocity. Keeping in mind the infintessimal mass of the earth, relative to the universe, the change would be almost unobservable.

Using Newtonian mechanics, the mass of the universe is irrelevant to the change in angular velocity of the earth from an oblique meteorite impact. All that it depends on is the relative masses and velocities of the two bodies and the geometry of the impact. Presumably under the Geocentric theory, the mass of the universe would be similarly irrelevant. So the impact would indeed change the angular velocity of the universe. Other effects that change the length of the day also, in the Geocentric theory, change the angular velocity of the universe.

But you are missing the point of the difficulty. Before the impact, the meteoroid is not part of the earth and its atoms are not counted in the calculation of the earth’s center of mass. After the impact, the meteorite is part of the earth and its atoms are counted in the calculation of the earth’s center of mass. At what point do we start counting them? When the meteoroid strikes the earth? When it is ten thousand miles from the earth’s center? When it strikes the atmosphere–although this too is not definite? I need a criterion and a reason for the criterion.

  • Liberian

Ah but let’s assume that the earth is an immovable object and gets hit by an irresistible force? When the immovable meets the irresistible what gives? Or does existence cease as we know it? :o :rolleyes: :confused: :eek:

Phil P

Liberian:

We are moving in 17 different directions here. I do not think we are communicating our ideas to each other very effectively.

First of all, what kind of modelling are you talking about? Have you done any modelling? You only get out of a model what you put in. There is no comprehensive single mathematical model of the universe.

Most of my professional experience with modelling is in the areas of structural, thermal finite element modelling and computational fluid dynamics. I suspect you are discussing kinetic modelling?

Let’s start with Gary Hoge’s model. I do not know what software he used, but I am pretty sure he did not model the earth. The earth is likely represented as a mass and a radius. He then balanced centripital and gravitational forces to determine an orbital path.

This is a model. It is very limited. It does not take into account the possibility of a comet hitting the earth (which would change the earth’s mass and center of mass, and thus the satellites orbital pattern). In this case he assumed a condition for the earth and calculated based on the assumed condition.

Are you trying to develop a comprehensive cosmology here? That is somewhat invlolved.

By the way, allowing the center of mass to move slightly to accomodate additional mass is not the same as Corpencism. The earth can shake. This is different than orbiting and rotating. The new center of mass would then be the center of the universe because the universe will attempt to conserve the centrality due to the gyroscopic stabilization. Unless the center moves drastically, (and the universe will use its mass and momentum to avoid this), the earth will continue to exist. If it does move too much, the earth will be destroyed.

The stabilization acts on the center of the earth (not necassarily a point, there likely is some functionality to its action). The portions of the earth which are not acted on directly or strongly by the stabilization are still connected to the parts that are and the forces will be transmitted through the solid body of the earth.

Please start over by proposing what type of model you are talking about. Please try and give me an example of such a model.

To me the important thing is the physics. Once the physics are defined, all kinds of models can be created.

[quote=trth_skr]Liberian:

We are moving in 17 different directions here. I do not think we are communicating our ideas to each other very effectively.

First of all, what kind of modelling are you talking about? Have you done any modelling? You only get out of a model what you put in. There is no comprehensive single mathematical model of the universe.

Most of my professional experience with modelling is in the areas of structural, thermal finite element modelling and computational fluid dynamics. I suspect you are discussing kinetic modelling?
[/quote]

trth_skr,

Actually I have been doing modeling and simulation professionally for about 20 years. My PhD was in computational fluid dynamics but I also have a good bit of experience in dynamic modeling, infrared (somewhat out of date), and so on, but much of my recent work has been in getting different sorts of simulations to talk to each other.

What I am trying to do here is establish a definition. I thought that Geocentricism states that the earth is stationary and that the rest of the universe moves around it. I am trying to establish exactly what it is that remains stationary. I’m not really modeling anything here; I’m trying to figure out what needs to be modeled. This is more basic than anything I have read under Gary Hoge’s name.

By the way, allowing the center of mass to move slightly to accomodate additional mass is not the same as Copernicanism. The earth can shake. This is different than orbiting and rotating. …

You are absolutely right that shaking is different from orbiting and rotating. But if Geocentricism states that the earth is stationary, by which it means not moving, then allowing it to shake is not Geocentricism. And this is why I keep homing in on the question of exactly what it is that remains stationary in the Geocentric theory.

  • Liberian

[quote=Liberian]trth_skr,

What I am trying to do here is establish a definition. I thought that Geocentricism states that the earth is stationary and that the rest of the universe moves around it. I am trying to establish exactly what it is that remains stationary. I’m not really modeling anything here; I’m trying to figure out what needs to be modeled. This is more basic than anything I have read under Gary Hoge’s name.

You are absolutely right that shaking is different from orbiting and rotating. But if Geocentricism states that the earth is stationary, by which it means not moving, then allowing it to shake is not Geocentricism. And this is why I keep homing in on the question of exactly what it is that remains stationary in the Geocentric theory.

  • Liberian
    [/quote]

OK, this is a more basic place to start.

There are many theories of Geocentrism. What I am advocating is not as rigid as you seem to apply. The Holy Spirit has guided the Church in defending that the earth does not move (rotation and orbit around the sun) and that the sun does move (around the earth).

The Church has held Geocentrism as a theory which upholds these principles, and has made statements about Geocentrism itself.

The Geocentrism I am advocating operates under the same physics as heliocentrism theories or acentrism.

As to where are the boundaries of the earth?

They would be the same as any other theory. If you think about it this is not an easy thing to define. Is it the point in the outer atmosphere where the density is 99.9% of the mean density at the equator? Do you want a definition of the solid boundary? This is more important in terms of how forces are transmitted through the earth.

Don’t try and make Geocentrism into a china doll. It operates under all the same scientific, philosophical, and logical rubrics as any other cosmological theory.

[quote=trth_skr]OK, this is a more basic place to start.

There are many theories of Geocentrism. What I am advocating is not as rigid as you seem to apply. The Holy Spirit has guided the Church in defending that the earth does not move (rotation and orbit around the sun) and that the sun does move (around the earth).

The Church has held Geocentrism as a theory which upholds these principles, and has made statements about Geocentrism itself.

The Geocentrism I am advocating operates under the same physics as heliocentrism theories or acentrism.

As to where are the boundaries of the earth?

They would be the same as any other theory. If you think about it this is not an easy thing to define. Is it the point in the outer atmosphere where the density is 99.9% of the mean density at the equator? Do you want a definition of the solid boundary? This is more important in terms of how forces are transmitted through the earth.

Don’t try and make Geocentrism into a china doll. It operates under all the same scientific, philosophical, and logical rubrics as any other cosmological theory.
[/quote]

trth_skr,

Now we are moving from science into theology. This really would better suit a new thread; this thread is about the length of the day and the non-rigidity of the earth.

I don’t have a problem with Geocentricism being considered to be true as an approximation. I use it all the time, whenever I say “The sun is setting.” The problem I have is that it is being proposed as the correct alternative to more conventional cosmologies which are presumed wrong. The geocentric theory was a good starting point; the Copernican solar system was better and the Keplerian better still, because its theory explained more motions with fewer equations. Newtonian mechanics is close enough for many calculations, as Geocentricism is also close enough for many calculations. In my job several years ago I calculated air vehicle trajectories assuming a flat earth. But I would never hold that the round-earth theory is wrong because of it.

The questions about what coordinate system is stationary and what atoms are considered to be part of the earth are relevant only if Geocentricism is taken to be a final and completely accurate theory, more accurate than general relativity and the Big Bang theory. If a proponent is going to make that sort of claim, he needs to be ready to answre that sort of question.

  • Liberian

I can’t believe that such obviously intelligent people are still so easily taken in by the relativistic nonsense promulgated by the heirs of Newton. This siderial day nonsense will be the downfall of human civilization if you don’t straighten up. No one would believe it at all if they just listened to reason, but the media is controlled by the international cartel of cocaine smuggglers in cahoots with the Ronald Reagan/Margaret Thatcher thugs who control Washington and London from the underbasement of the White House (and who had Lyndon Larouche thrown in jail for no other reason than his unauthorized use of their credit cards!) and they won’t print any of my letters ot the editor, would’ya believe it??
:banghead:

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