Is Gravity Caused by the Motion of Particles in the Fabric of Space?

[heusdens]

Originally posted by Mr. Robin Parsons
Don't need to, as you are using a system that doesn't apply to the reality as you keep assuming that you can simply ignore the fact of all of that mass that the waves of gravity would need to pass through, to get to each other, to cancel.

only works in the math department, NOT in the reality of the measured physical planet, as proven by the large steel ball known to be at it's center.

The "steel balll at the center" is neither a proof for your ideas nor a disproof of the fact that at this center, the force of gravity, or the acceleration of gravity, is zero.

And "gravitation waves" were never observed. Besides, it is a property of waves that they can cancel, as proved by interference of light.

That was why I had previously brought up the 'Lagrange' point thing, to demonstrate what happens to a mass that is in a place where G = zero, it is pulled towards the nearest thing that has G energy/force, and away from the zero G point!

Just because you can mathematically cancel out all of the factors on a sheet of paper, does not prove that the planet behaves that way, especially when, in that paper proof, you are functioning in a manner that ignores completely the fact that the mass is full, of mass, not some hollow, partially empty shell, that you have drawn, on a sheet of paper.

BTW, I can, by God's Grace, imagine lots of things, that does not make them real, just imagined. This is supposed to be a discourse on the reality of it, not the imagined of it.

Yeah. So when do you srart digging that hole! We are just waiting for you to come up with some proof!

Btw. What is this G = 0 thing? G is the gravity constant, which is never and nowhere zero. Perhaps you mean g, the gravitational acceleration?

Mass is full of mass... hmmmmmmm Well that explain what mass is, isn't it?

It refers to what you are also. You are full of yourself!

 

[heusdens]

Mr Parson, please go on with your weird and revolutionary ideas.
It really is ammusing to all of us. Such fun!

Perhaps instead of criticizing mathematics and physics ideas, better try and learn to understand them!

 

[yogi]

The formulation derived by Nigel is idential to Friedmann's equation except for a factor of 2 - this does not prove that gravity is caused by expansion - it is a relationship between the deceleration of the universe due to the retarding effect of the totality of cosmic matter. Friedman's equation for critical density
[rho = 3H^2/8pi(G)] is the same. I would agree however that gravity is a consequence of expansion - I derived an identical formulation about 10 years ago based upon expansion. This was published on the net for some time under the name "Cosmodynamics"

 

[heusdens]

Originally posted by Nigel
With the fabric of space, exactly the same thing is produced by the big bang: the fabric of space presses towards us because the clusters of galaxies are accelerating away (with a speed proportional to their observed distance). This pressure causes gravity as I prove, getting the law plus a formula to calculate the constant G which was never done before. My argument is that having got this formula, the problem is solved.

There is something wrong with this explenation. The Big Bang was not like a material explosion (matter speeding away from a precise location at varying speeds) in pre-existing space. Actually the Big Bang is the expansion of spacetime itself.

Originally posted by Nigel
Proof of the cause of gravity as the effect of the Hubble expansion on the fabric of space. The outward motion of matter is balanced by inward directed fabric of space, maintaining a full volume, just as air moves into a suitcase when you take clothes out of it. The pressure towards us produces gravity by pushing us from all directions equally, except where reduced by the shielding of the planet Earth below us.

The Hubble expansion is caused by gravity. How can there be Hubble expansion without gravity?
Now if what you say is true, then while gravity still causes Hubble expansion, now the Hubble expansion causes gravity.

Your argumentation is fully circular. So, I don't expect that you found the cause of gravity, you only found a different way of expressing how this force works.

 

[yogi]

Huesdens - it isn't really necessary to involve the early universe in the mathematics of Nigel - simply consider the present state of the universe as a spherically symmetrical expansion - take the volume and differentiate twice - this gives you the volumetric acceleration (8piRc^2) - then make a volume to surface transformation using the divergence theorem (this simplifies to dividing by 4piR^2 for a sphere) - so the effective isotropic acceleration is 2c^2/R - from here you can get to Nigels result. Note that Nigels formulation predicts that G varies with time - When I first arrived at this result some years ago it bothered me because the experiments show G to be constant - but the problem is that all the experiments are measuring the MG product - not G alone - that is they measure orbital consistency of satellites over a period of years.

 

[heusdens]

yogi -- I hope you see the point of my argument... The theory of Nigel is based on the Hubble expansion. The theory states that this expansion can explain the cause of gravity. However, the Hubble expansion itself is an effect of gravity. So, we have gravity, causing Hubble expansion, and Hubble expansion then causes gravity.
How can something be it's own cause?

 

[yogi]

Agreed heusdens - you can't pull yourself up by the bootstraps - I think the fallacy is in the assumption that gravity is the cause of expansion - if you use the zero energy (null) model of the universe first advanced by Ed Tyrol some years ago, expansion can be thought of in terms of the dynamic necessary to balance the negative potential energy with Kinetic energy - in which case the universe must have critical density. Accordingly, if expansion is a consequence of energy considerations - then the assumption re gravitational cause is erroneous. In the equations of Freidmann gravity comes in as a retarding influence - not a source of expansion. Given this caveat, the equations relating the cause of gravity to expansion make a lot of sense - recall the units of G (Vol acceleration per unit mass). I would disagree with the pressure analogy however - and the shielding idea of matter - it is much more logical to simply consider gravity as opposite side of the F=ma coin - in the case of a mass accelerated with respect to space - we get an inertial force - in the case of space accelerated relative to a mass - we also get an inertial force - but since the acceleration of space is so small, we need a lot of mass to get much of an effect. This also explains why gravitational mass and inertial mass are identical (Einstein's equivalence) and it comports with Einsteins postulate that we would get the same force effect if the universe were accelerated with respect to a hunk of matter as we would get if the matter were accelerated relative to the universe

 

[Mr. Robin Parsons]

03/06/2003

So heusdens, and Brad_AD23, just checked a reference source and found a reference to the fact of the outer (liquid) cores convection of heat by "material transportation", simple words, the outer molten core of the planet convects heat towards the mantle shell, above it, because, hotter, therefore lighter, materials rises towards the mantle.

It would also follow that heavier/ denser, cooler, materials, fall back towards the inner, solid core, and this evidence is in complete contradiction to the "theoretic" that you have attempted to defend.

If the gravitational acceleration was cancelled, as you seem to wish to tell me it is, then the site of the highest gravitational attraction, is the mantle to inner core boundary layer.

If your postulate was in fact correct, then the heavier materials would flow upwards from the inner core/outer core regions, towards the mantle, and the lighter, therefore less gravitationally acted upon, materials, would flow downwards, towards the site of lesser gravitational attraction, towards the inner core.

This is NOT what the physical evidence tells us is happening. The PHYSICAL EVIDENCE tells us that the hotter/lighter materials travel up towards the mantle, and the heavier/cooler materials flow down towards the inner core.


So the reason why I keep at this, in this manner, is simple enough, the reasoning that you have been trying to convince me, is working, in the earth, goes like this, mathematically.

Your first statement is that all of the mass of the Earth contributes to the resultant measure of the G force at the surface...mathematically you are doing this...

Eq # 1 (2 + 2 + 2 + 2 + 2 + 2 + 2 + 2 + 2 + 2) = 20

Then you want to tell me that you have self cancellation, within the Earth itself...which is this math

Eq # 2 (2 + 2 + 2 - 2 + 2 - 2 + 2 - 2 + 2 - 2) = 20

Please note, the result of the second line is, according to your statements, still 20! as you would wish me to follow (somehow) that you can 'self cancel' a vast amount of the mass's contribution to the energy that is seen as gravitational attraction, and still have the same resultant measurement of the force of attraction that is the 'Earth Normal' G force.

That is a sophist's fallacy!

Heusdens, it surprises me not that you would recommend that I return to preschool, as apparently, you being the evidence of a 'recent graduate' of such an institution, demonstrate clearly the need for someone to go there and explain to the people, who taught you, that mathematics simply does not work that way .

So the choice is clear enough, either it is the Eq. # 1, Or the Eq # 2 (if you think it's both, well, see the statement emboldened just above)

If # 1 then the force of gravity goes all the way to the center of the planet and DOES NOT self cancel, the measure of G, at the core, is NOT at zero! (as you would want me to believe)

That one is clearly my choice, and I would add that the method of measurement of the Force of gravitational attraction going in would be 1/ square root of r

If it is # 2, then, there is/are several problems, one being the fact that the amount of mass that is generating the surface measure of the acceleration due to G, is way off, and the amount of mass that the planet contains, needs be way higher then what is currently "known".

And, that problem includes the problems of the density, as now you need to compress an enormous amount of mass, into a smaller space, to effect that "G" reading.

Further to that problem, in the convection problem, stated at the outset of this piece.

Further to that problem, comes this problem, the depth v pressure readings that do NOT concord with the facts of the gravitational attraction.

It cannot be both statements eq #1 and eq # 2, not a chance!

In a graphic of the pressure v gravity that I have been looking at, the (acceleration due to) gravity actually increases, from Earth 'Normal', to ~11 m per s^-2, at a depth of ~1800 mi/3000 km, then, (apparently) drops off to "zero" as it goes towards the center.

But the pressure does a relatively steady climb, all the way down, continuing to climb, past the above indicated depth,without any method of pressurization.

Case you haven't grasped it yet, matter/mass is compressible, by gravitational activity, as is very clearly demonstrated by large, Stellar objects, and by Black Holes.

How you develop that kind of pressure, 3 to 4 mbars, without any method of pressurization, (as in your scenario, gravity has stopped accelerating everything/anything) is simply beyond me, and beyond you too, (I suspect) just that, I sincerely doubt that you will admit to that.

So, it is nice, (I suppose) that you tell me that I can lead a revolution in Science, just that, unbeknownst to you, that has been going on, for some time now, so I never needed, nor sought, you permission, for that endeavor. (Clearly, you were "out of the loop", and, God willing, will remain so!)

As for the rest, well, clearly, your "pressed" postulate has enough holes in it, to drive a truck through it, (I would know, I used to do that, drive trucks, big ones!) so I would respectfully suggest that you return to your vector map, and realize that, just because you can cancel out the two "equal and opposite vectors" that arise from two cars driving towards each other, at equal speeds and opposing directions, does not mean that they will not crash together with zero force.

(And please, don't go out and test that, cause the thing that probably gets "zeroed" in that scene, is the driver!)


PS If you would bother to do the calculation, you would find that, if you employ 1/square root of r as the manner of measure of Gravitational acceleration towards the center, you will find that the increasing gravitational activity, matches the pressure gradient, quite well!

 

[Brad_Ad23]

Parsons you STILL don't get it. What we say accords exactly with stuff falling. We ARE NOT saying gravity simply vanishes. We are saying that the vectors for gravitational force cancel out exactly at the Earth's center of gravity. There is a world of difference between saying "gravity ceases to exist and gravitational vectors cancel out."

 

[Mr. Robin Parsons]

Originally posted by Brad_Ad23
Mr. Parsons you STILL don't get it. What we say accords exactly with stuff falling. We ARE NOT saying gravity simply vanishes. We are saying that the vectors for gravitational force cancel out exactly at the Earth's center of gravity. There is a world of difference between saying "gravity ceases to exist and gravitational vectors cancel out."

In several of the postings herein you have adamantly and repetitively told me that the gravity at the center is zero, aside from that, I already know that you are simply following current theory, as the site I spoke of, has the exact same thing, in it's graph of pressure v gravity.

Between the two of you, it is like having a "dog on my leg", not even cognizant enough to know that it's the wrong species!

What you have stated does NOT accord with suff falling, as clearly the gravity is higher, according to what you have both been shoving on me, above the center, Hence it could do nothing but "fall up", and it doesn't!

Point closed, end of any further use of my leg! (get it?)

PS. current theory is wrong, big deal, live with it, cause all it really changes is your minds, nothing else! (Oh and BTW, just read a really good article on gravitational collapse, neutron stars, black holes, etc, and they all would not function that way if the gravity fell to zero at the center of the masses there. Heck the pegged a neutron stars density a 10E14 to 10E15 times the density of water, in a 6 mi (10 k) radius, you think something like that has a gravitational force that drops off to zero in it's center, WOW, it's the gravity that is doing the pressurization! nothing else could! Oh yes, another BTW, WHEN I TYPE IN CAPS IT IS FOR EMPHASIS ONLY, I HAVE NO NEED TO SCREAM AT ANYONE, BUT WHEN YOU DO IT, WELL, I AM PROBABLY GRATEFUL, AS I NO LONGER NEED MY GLASSES TO READ YOU, SOMETHING ABOUT BEING ABLE TO CONTROL YOUR OWN MIND, A JEDI 'TRICK', (no doubt) TEE-HEE-HEE-HEE-HEE-HEE-HEE-HEE-hee-hee-hee-he, as I had overheard, Jedi Jokster!)





BYE!

 

[Chemicalsuperfreak]

Maybe this has already been answered.


Mr Parsons, consider an empty chamber in the center of the Earth and at time 0 an apple is suspended in the exact center. Now according to you, there is still gravity, so my question is, does the apple fall towards China or America?

 

[Brad_Ad23]

I guess that's why it takes a physicist to realize that zero need not imply the absence of something. Then again, I suppose having an inflated ego enough to think you are more correct than many centuries worth of people who have studied many years and know the subject intimately. Good for you.

 

[yogi]

All experiments and all textbooks confirm that the gravitational field E falls off inversely with radius inside a homogeneous spherical mass, that is since E = GM/r^2 and since
M = (rho)V then E = G(rho)[4/3]pi(r^3)/r^2
therefore E = (4/3)(rho)(pi)r

What has all this got to do with the parent subject - namely the proposition that G is determined by expansion. I would comment also that the criticism of the theory based upon GR is unfounded - the derivation is for the coefficient G that appears in both the Newtonian and Einsteinian formulations - neither man could come up with an explanation of why G has the value it does. This should be the focus of the inquiry -

 

[heusdens]

I agree with the previous post, this whole discussion with Mr Parson, is off-topic, and not relevant to the issue of this thread, which is about the cause of gravity.

We should probably dedicate a whole new forum to the issues mentioned by Mr Parson. It would be the "educate Mr Parson" thread, cause from his posts it is clear, he hasn't the slightest understanding of the subject matter.

He keeps talking about G (gravity constant), while the issue at hand is gravity acceleration, and nothing else.

And he keeps thinking, that matter would accelerate at the center of gravity in the direction of the surface, while this is a simple impossibility (it can't spread out in all directions simultaniously).
If there is no nett force of gravity at the center, it means no acceleration, and not acceleration in the opposite direction.
Things fall "down", cause by definition down is the direction towards the center of gravity.

 

[heusdens]

Mr. Parson -- What happens if you put two exactly equal trucks front-to-front, with their bumpers touching each other, and both trucks would have their engines exert an equal force.
Well the fact is that besides a lot of noise, the slipping of the wheels, etc, nothing happens, that is, the two trucks won't move an inch (provided the forces exactly balance).

So, my notion of all this is: see, there is no NETT ACCELERATION, but there are forces, which exactly balance at that point.

 

[heisenberg]

General relativity failed to predict the recession speeds of distant supernovas1.

Einstein put the terms in the field equations, but later retracted them, under pressure from the Hubble red-shift discoveries! (His greatest blunder)

 

[yogi]

heisenberg - i would not bet on the fact that GR failed to predict the corret recession speeds - as interpreted by distant 1a supernova - there are other explanations for the apparent dimming that is taken to be evidence of accceleration - things might have been different when the universe was younger - the factors that determine when the supernova event occurs are complicated - and anyone of them could conceivable lead to different dynamic conditions - for example, the very essense of this thread concerns whether G is constant - according to the expansion theory of gravity, G must be a variable if the expansion rate is always c - so if G were greater in the past, the supernova event might well be triggered with less mass and hence the apparent brightness would be less (not due to a greater distance but to a smaller mass than what is required for a contemporary supernova).

 

[Mr. Robin Parsons]

Originally posted by heusdens
Mr. Parson -- What happens if you put two exactly equal trucks front-to-front, with their bumpers touching each other, and both trucks would have their engines exert an equal force.
Well the fact is that besides a lot of noise, the slipping of the wheels, etc, nothing happens, that is, the two trucks won't move an inch (provided the forces exactly balance).

So, my notion of all this is: see, there is no NETT ACCELERATION, but there are forces, which exactly balance at that point.

Your notion is what I have been telling is the answer, lots of force at the center, but that force arises from the accelerative nature of gravitational force, as it is not zero at the center, and it does NOT drop off as you approach the center, as it is gravity that provides/makes the pressure that is found there.

Originally posted by Heusdens

And he keeps thinking, that matter would accelerate at the center of gravity in the direction of the surface, while this is a simple impossibility (it can't spread out in all directions simultaniously).
If there is no nett force of gravity at the center, it means no acceleration, and not acceleration in the opposite direction.

So once again, (according to you) an object that is gravitational, will NOT move towards the spot where gravitational acceleration is greatest, somehow it will resist this motion, and without any forces acting upon it.

Sorry, don't buy that!

Originally posted by Chemicalsuperfreak

Mr Parsons, consider an empty chamber in the center of the Earth and at time 0 an apple is suspended in the exact center. Now according to you, there is still gravity, so my question is, does the apple fall towards China or America?

Firstly, I see that you too see that it must Fall up, aside from that, it would fall in the direction of whatever imperfection in the non absolute sphericallity, that it has, that causes the slight influence that will begin it's acceleration towards the greater gravitational pull, either from it's own gravity, or from the greater gravitational attraction, that is above it, proven by the greater gravitational acceleration that can be measured there, according to these two other guys, NOT according to me.

But it answers your question, as anyone with "The Proof of the cause of Gravity" should be able to answer this entire issue, without question.

 

[Mr. Robin Parsons]

6/5/2003

So in the example given by Heusdens of the two trucks in opposition, what I am attempting to explain to you, jargon aside, is that the force which is the gravitational force, (which arises from the acceleration due to gravity) is still operating at the center of the planet.

This is proven by the very simply observation of the pressure that IS there, as it is also very obvious from Heusdens example of the two trucks, as they are exerting pressure at their interface.

That the acceleration due to gravity is not observed (observable) does not mean that there is NO gravitational force at work, there is, same as it is very clear that the two truck are exerting force against each other. The resultant vector of acceleration is zero, but the vector of force is not cancelled, it is what generates the pressurization that the two truck are creating between them.

The idea that energy generates force is clear enough from the flashlight upon a scale, it gives a reading, therefore we know that it is able to generate a force, that is the same thing that gravity is doing at the center of the planet, generating a force, not an acceleration, and the force at that level is measurable as the pressurization of the matter.

Gravity is what is pressurizing the mass, all the way through to the center of the planet!

Measurable as 1/√r (Actually Gm/√r)

EDIT Sq rt of changed to √

 

[heusdens]

We never had a disagreement about pressure inside earth, and the fact that gravity works down there as well.

The only dispute was wethere there is a NETT RESULTANT force of gravity, a nonzero gravity acceleration right at the center of gravity of earth.

That is what you argued against.

Do you accept my proof now?

Nett force of gravity, resultant acceleration due to gravity at the center of eart, is zero, at the center of gravity.

End of discussion.

 

[Mr. Robin Parsons]

No, there is still force being applied by gravity, it is what is causeing the pressure that is there.

No 'acceleration', meaning 'no motion/movement', but the "accelerating energy" (generating a force) is still very active there, it is what is generating the pressure.

To that, I will agree.

PS Heusdens, please stop quoting my entire posts, uselessly/needlessly, that is a waste of server space Thanks, in advance!

 

[Chemicalsuperfreak]

Originally posted by Mr. Robin Parsons
No, there is still force being applied by gravity, it is what is causeing the pressure that is there.

No 'acceleration', meaning 'no motion/movement', but the "accelerating energy" (generating a force) is still very active there, it is what is generating the pressure.

To that, I will agree.

PS Heusdens, please stop quoting my entire posts, uselessly/needlessly, that is a waste of server space Thanks, in advance!

f = ma

No net acceleration means no net force. Gravity or otherwise.

 

[heusdens]

So, we agree there is no nett accelartion, so no nett force.

THANK YOU VERY MUCH!

 

[Mr. Robin Parsons]

Originally posted by Chemicalsuperfreak

No net acceleration means no net force. Gravity or otherwise.

So according to you, in Heusdens example of the two trucks 'facing off', since there is no acceleration, you see it as a situation with "no forces" at work, at all.

Clearly I disagree.

Aren't you missing the fact that the 'force(s)' are in opposition and are, therefore, generating a pressurization/pressure. (respective of the balance held)

Tell me something simpler Heusdens, have you ever bothered to examine any other alternatives to the theory you already know, listened to an explanation, in full, of why there is a more appropriate/apt description of the "event(s)", that satifies all of the required needs of the observed activities?

 

[Brad_Ad23]

Parsons, yes it does generate a pressure. Remember, pressure is force over area. Since there is a quantity of force in there, there must be pressure, we agree. But that is irrelevant since the pressure does absolutely nothing to alter the system. The two forces still cancel out and there is no net acceleration. Please remember Newton's 3rd law of motion and you may be better able to see why the pressure does not matter.

 

[heusdens]

Mr. parson, have you really tried to understand physcics?

 

[r637h]

"If a fool be silent..."

Is gravity at the "exact" center of a body net=0?

Well, I believe gravity refers to the "whole ball of wax", as it were.
The center of a body is simply a convenient point of reference, especially when it defines the relationship to an (interacting?) body.

I suppose the argument is whether it's calculable. It may be, theoretically, but it's not observable, or measureable. The measuring device could not function independantly of that being measured (the old canard), even for Classical Physics.

Mez Pas?

 

[heusdens]

There are supposedly convections streams down there.

 

[Mr. Robin Parsons]

Originally posted by Brad_Ad23
Parsons, yes it does generate a pressure. Remember, pressure is force over area. Since there is a quantity of force in there, there must be pressure, we agree. But that is irrelevant since the pressure does absolutely nothing to alter the system. The two forces still cancel out and there is no net acceleration. Please remember Newton's 3rd law of motion and you may be better able to see why the pressure does not matter.

So Brad_AD23 you think the pressure is "irrelevant"

From the 'subscription' site "Access Science", Mc Graw-Hill.

"High-pressure physics is concerned with the effects of high pressure on the properties of matter. Since most properties of matter are modified by pressure, the field of high-pressure physics encompasses virtually all branches of physics."

"The major effects of high pressure on matter include diminution of volume, phase transitions, changes in electrical, optical, magnetic, and chemical properties, increases in viscosity of liquids, and increases in the strength of most solids."

Authors; R. K. Linde P. S. DeCarli

Copyright ©2000, 2001, 2002 The McGraw-Hill Companies.

You should answer the question of your "twin:" here, Heusdens question...

Originally posted by Heusdens

have you really tried to understand physcics?

As for you r637h, whomever you are, the Bible counsels not to go looking for fools, good counsel, you should follow it.

"Better to keep your mouth shut, as be 'thought' of as a fool, then to open your mouth, and prove it!"

 

[Mr. Robin Parsons]

Originally posted by heusdens
There are supposedly convections streams down there.

BTW heusdens, on/in the site, that I have cited work from above, the gravity v pressure graph put the acceleration due to G at ~11 or 12 m/sec^-2, at around the boundary of the mantle, and the outer liquid core.

That figure indicates that if a heavier object were towards the center, acceleration due to G < ~11 or 12 m/sec^-2 (WAY less then, more like 1 or 2 m/sec^-2) then the heavier object should, according to the principles of (sound/solid) physics, migrate towards the Higher gravitational accleration, which means heavier/denser objects should be floating Upwards, as the acceleration due to gravity up there is much higher then down there.

Therefore, so should the thermal plumes, flows of heated matter should be flowing down for the hotter lighter, less dense materials, and up for the heavier cooler denser materials.

Opposite to the manner in which it is known to occur!

But that is only according to your insistance, here, in this thread.

 

[Brad_Ad23]

Notice, I said the pressure was irrelevant to the SYSTEM. Much different than saying pressure is irrelevant. Why? Because I said it was irrelevant to the system being described. Key word: system. Of course, I suppose you just didn't catch that, did you?

 

[r637h]

"If fools be silent..."

Whoever I am, I did not intend the quote to apply to anyone in particular, and certainly not as a criticism

The literal quote is in Proverbs 17:28.

Beg pardon for intruding. "...and the rest is Silence."

 

[Mr. Robin Parsons]

Originally posted by Brad_Ad23
Notice, I said the pressure was irrelevant to the SYSTEM. Much different than saying pressure is irrelevant. Why? Because I said it was irrelevant to the system being described. Key word: system. Of course, I suppose you just didn't catch that, did you?

Notice in the manner in which I had quoted you, the word 'system' is there, as in "Yes", I had noticed, and Yes, it is relevant, just that, apparently, you don't think so, That Proves nothing.

Sorry r637h, had mis-read it I guess.

 

[Brad_Ad23]

Parsons, first of all, the system I am referring to is the truck example, not the Earth one (since that follows from the truck idea). Second of all, the website notes that it is HIGH pressure. The pressure generated by the two trucks is hardly high enough to alter properties of matter, lest the trucks start acting very strangely.

Now, notice the Earth is high pressure, and nowhere do we say pressure is irrelevant. Indeed, the balance the pressure has by representing a force directed outwards to counter gravity is quite important. I also find it rather odd that you go to all these sites, one would think that somewhere you would encounter some argument you could comprehend as to why the rest of us are right. But again, I reiterate, since you are so convinced you are correct, I look forward to reading about your works someday.

 

[Mr. Robin Parsons]

And Brad_AD23 in the posting right above mine, Heusdens, the person I was originally addressing, stated...

Origianlly posted by Heusdens

So, we agree there is no nett accelartion, so no nett force.

So please, follow what is being talked about, or please, stop talking.

Thanks.

 

[Brad_Ad23]

But you also were referring to the truck example as well.

At any rate, the mechanics, and this may surprise you, work the exact same way regardless of the location.

 

[Mr. Robin Parsons]

Originally posted by Brad_Ad23
But you also were referring to the truck example as well.

At any rate, the mechanics, and this may surprise you, work the exact same way regardless of the location.

Ahem, no I wasn't, and why would the "Mechanics of it" surprise me?

The point that I was making with Heusdens was concerning the measure of gravitational 'force' being excerted at the center.

He said "No Acceleration, no Force", I said "No acceleration, but still Force" which is where the pressure results from.

You seem to think that somehow the Earth's shell is pressurizing it's center, which would indicate that a Neutron Star's contraction would spew matter, out into the universe with tremendous force, as it would somehow be this "shell structure" you two keep inferring gravity makes, snapping into pieces as it attempted to contract, because in your world it DOES NOT contract from the center, it contracts from a shell ~4/5^ths of the way down from it's surface...same as the earth's.

That is 'patently' WRONG!

EDIT a comma, like that one, there, behind , here (yuk yuk)

 

[Brad_Ad23]

Ok, here is some math to back this up also:

http://burro.astr.cwru.edu/Academics/Astr221/SolarSys/hydrostat.html

http://dept.physics.upenn.edu/courses/gladney/mathphys/java/sect5/subsubsection5_1_1_2.html



Also to note, it is nuclear fission (radioactive decay) that heats up the Earth primarily, not pressure.

And, to note also, no matter what, the sum of the gravitational forces at the center is zero. But as we have been trying to say, this does not mean that nothing is happening. Zero net force is not the same as absence of force. A simple analogy:

Take the Earth and divide it into two equal parts. Seperate it some distance and put yourself at the center between the two hemispheres. Since the gravitational attraction cancels out, you won't move. BUT, stay there for a few minutes and the two hemisphere will come together and crush you with a pressure proportional to the force of attraction between them and your surface area. Does that perhaps better clairify how no net force can still exist in the presence of pressure?

also: I am not quite sure where you get a 4/5th from nor this shell pressurization. And as for the truck stuff, perhaps a contextual misread. At any rate, the above situation dealing with the force of gravity and pressure is physics. A simple bit of research will show that.

 

[r637h]

There's no way to be totally silent: It's against human nature.

I only want to say (for now) that I find the dialog (multilog?)
in this thread absolutely fascinating. Mirable dictu! I think I'm actually learning something.

Best regards to All.

 

[Mr. Robin Parsons]

Originally posted by Brad_Ad23
Also to note, it is nuclear fission (radioactive decay) that heats up the Earth primarily, not pressure.

And, to note also, no matter what, the sum of the gravitational forces at the center is zero. But as we have been trying to say, this does not mean that nothing is happening. Zero net force is not the same as absence of force. A simple analogy:

Take the Earth and divide it into two equal parts. Seperate it some distance and put yourself at the center between the two hemispheres. Since the gravitational attraction cancels out, you won't move. BUT, stay there for a few minutes and the two hemisphere will come together and crush you with a pressure proportional to the force of attraction between them and your surface area. Does that perhaps better clairify how no net force can still exist in the presence of pressure?

also: I am not quite sure where you get a 4/5th from nor this shell pressurization. And as for the truck stuff, perhaps a contextual misread. At any rate, the above situation dealing with the force of gravity and pressure is physics. A simple bit of research will show that.

According to your source for the pressure, they 'average out' the density, hence it is not looking for from where the pressure is generated, nor does it give a result in concordance with what I have/had, the Access Science site's graph told me between 3, and 4 Megabars of pressure at the center.

Your is 1.7x10E6 atmospheres, which, when I convert from Megabars to atmospheres, I get @ 3 megabar = 2,960,769.5079428 atmosphere [standard] and @ 4 megabar = 3,947,692.6772571 atmosphere [standard], so I would respectfully suggest that your site is simplfieing the math just a little bit much.

The part of your post that I have emboldened is self-contradicting as you first tell me the gravitational attractions cancel, then, that they will crush me.

Your problem is a simply one you keep treating gravity as if it can be dealt with as a 'discrete' force, "pieces and parts" of what acutally acts in a wholistic manner.

Where do you see that pressure coming from?, arising from?

The "4/5^ths" was explained, in one of my posts, some pages back.

 

[heusdens]

Originally posted by Mr. Robin Parsons
Ahem, no I wasn't, and why would the "Mechanics of it" surprise me?

The point that I was making with Heusdens was concerning the measure of gravitational 'force' being excerted at the center.

He said "No Acceleration, no Force", I said "No acceleration, but still Force" which is where the pressure results from.

You seem to think that somehow the Earth's shell is pressurizing it's center, which would indicate that a Neutron Star's contraction would spew matter, out into the universe with tremendous force, as it would somehow be this "shell structure" you two keep inferring gravity makes, snapping into pieces as it attempted to contract, because in your world it DOES NOT contract from the center, it contracts from a shell ~4/5^ths of the way down from it's surface...same as the earth's.

That is 'patently' WRONG!

EDIT a comma, like that one, there, behind , here (yuk yuk)

Yes Mr Parson. And you have an ABSOLUTE TALENT for not understanding what someone else is telling you.

The discussion was not about wether or not there is the force of gravity at the center, but wehter there is a NETT RESULTANT FORCE.
And there isn't since all forces balance there, and hence no gravitational acceleration.

Else I didn't claim, and especially this pressure thing, I never claimed there not be a lot of pressure there.

 

[Mr. Robin Parsons]

Please stop wasting server space!

2003-06-08

Lets try it this way Guys, F = ma, so, when I hold a golf ball in my hand, balanced forces, no acceleration, I "drop the ball" (so to speak) and gravity continues to act upon the mass that was previously in a 'balanced holding', by accelerating it towards, and into, the ground.

Gravity continues to act, holding the ball securely to the face of the planet.

From that we can deduce that, the acceleration has ceased, but gravity is still excerting a force as to hold the ball to the face of the planet. We can measure that force, easily, by simply inserting a scale between the interface of contact, and we now see that the energy of gravity, being opposed by a greater resistance, generates a pressure we call "Mass".

Gravity is still working, it has never stopped, not since the formation of the planet, it is inceassent, it is continous, and persistant, throughout time.

So in the equation F = ma, we need a repair, in our thinking, actually, because when gravity acts to hold a piece of mass/matter to it's gravitational face, we can easily surmise the action of a force, even though we see no acceleration, we still know that the effort/attempt of/to accelerate, exerts force called pressure, or weight/mass, so we need to see that in the Equation the acceleration value can only be seen as a 1 (one). (with NO qualifiers like m/sec²)


The reasoning is simply that, now we see that F = m(1), or F = mass, because we know that the fact of "mass" is as a result of gravities attempt at accelerating something, in a place where the opposition to that acceleration, is greater then the force applied, and we weigh that 'force', on a scale, and call it pressure, from a mass.

The force is the weight, the weight is a measure of a force, the force that is being measured is still gravity, just that like the two trucks at opposition, there is an attampt at acceleration, that generates a pressure, measurable with a scale, as either a pressure, or a mass, although we wouldn't normally recognize a reading "that way" as a mass, it is, effectively, the same thing.

(because you need "mass", to make pressure)

So we now see that gravity is a pressurizing force, a wave of energy that attempts to accelerate mass that is oppositionally resistive to that attempt at acceleration, the result of which is pressure(ization, of mass)

Try that one....

 

[FZ+]

Mr Parsons: But F = ma (or more accurately F d/dt(mv)) is applied only on the resultant force on the object. In the case of the object, there is not resultant force because the sum of the force of gravity "down" and the electromagnetic reaction force up is zero. It's not opposed by greater resistance, because then we would have an acceleration upwards.

 

[Mr. Robin Parsons]

Originally posted by FZ+
Mr Parsons: But F = ma (or more accurately F d/dt(mv)) is applied only on the resultant force on the object. In the case of the object, there is not resultant force because the sum of the force of gravity "down" and the electromagnetic reaction force up is zero. It's not opposed by greater resistance, because then we would have an acceleration upwards.

Static resistance, the sum of the forces is not zero, the measurable force is the weight of the mass, hence it's ability to exert pressure, as it so clearly does, like a six ton rock.

EDIT ...Like a six ton Rock, which, BTW, weighs in at one ton, on the Moon, because the Gravitationally attempted acceleration excerts 1/6^th (less) the force, upon the rock.

 

[FZ+]

No sir. When you are weighing, you are in fact weighing the difference in the two force vectors by their effect on both ends in compressing the scales. When you weigh the person, you are simultaneously weighing the planet in terms of the person's gravitational field.

 

[Brad_Ad23]

The Net (please for the love of physics learn what the word net means when applied to force!) force cancels out..ie. it is zero. This does not by any stretch of any good imagination mean gravity is not present. As has been stated numerous times by everyone but you, zero net force/acceleration can and does exist when two even forces balance out, but the two forces still exert a pressure, in the form of an equal but opposite reaction. Hence you are squished, but you don't move from one side to another.

 

[Mr. Robin Parsons]

Originally posted by FZ+
No sir. When you are weighing, you are in fact weighing the difference in the two force vectors by their effect on both ends in compressing the scales. When you weigh the person, you are simultaneously weighing the planet in terms of the person's gravitational field.

Ahem, you are 'weighing' the planet's gravitational attraction, as it acts upon the person.

If you remove the weight from the face of the planet, the planet does NOT come flying out at you, (a slight decompression may happen) as it affords no vector of "force", it affords a vector of resistance to force.

Brad_AD23, the 'zero net force' you would wish me to believe in, is wrong, simply on the fact of the energy, that is gravity, is still acting upon the matter, that is what is compressing it. Nothing else can.

Originally posted by Brad_AD23

As has been stated numerous times by everyone but you, zero net force/acceleration can and does exist when two even forces balance out, but the two forces still exert a pressure, in the form of an equal but opposite reaction. Hence you are squished, but you don't move from one side to another.

Not from what you and heusdens have been stating on these pages, as you keep trying to tell me that the center is at zero, less gravity there, according to BOTH of you, then above it, and the simplicity is that it is the Force, of the acceleration, due to the passage of gravitational energy, waveform, that is causing the compression of matter at that center.

Hence that waveform, energy, that is gravity, must still be acting right down to the center. Otherwise NO COMPRESSION.

 

[Mr. Robin Parsons]

look!, the past, it's catching up!

So Brad to recap yours and Heusdens arguements, "a brief history of time" (Sorry Stephan Hawking)

Originally posted by Heusdens pg 17

Right at that point, we imagine to have a whole bunch of vectors, in different directions and different magnitudes. Now the application of some math allow you to pick pairs of vectors with same magnitue and opposing directions, which sum to a resultant vector of zero magnitude, and the "proof" includes that this can be done in such a way that all the vectors can be removed. Resulting in this zero gravity force at the center.

and from page 16...

I don't have a massive pressure problem. I already explained what caused the pressure. It's because all the mass that DOES have weight ABOVE the center of gravity, that is pushing there.

There is absolutely no problem with that.

and from page 15...

It can be proven very easily however that right at the center, all forces of gravity of all the mass of earth, cancel out.
Now take any part of the Earth mass, and calculate this mass and it's distance to the center of gravity. That will enable you to calculate the force of gravity from that part of Earth's mass. Which is not zero. But at the exact opposite direction, we will find an equal mass at equal distance. This follows the fact that the density of Earth at any specific depth is more or less the same, and the Earth is a round spherical object. So we can deconstruct all of Earth's mass into small parts (as small as you want) and calculate the force of gravity from all parts. Since we always can find for every force vector an equal and exactly opposite directed force vector, this means that the resulting force of gravity exactly results in a force of zero.

And you Brad_Ad23

Originally posted by Brad_AD23 pg 14

Ok Parsons, listen up carefully. The gravitational force is directed downwards. To the center of gravity. At this point, the center of gravity, this is where all the little vectors of force meet up. At this point, there is no attraction, since there is no distance to go to get to the center of gravity. But, what else is going on? Hmm, well we have all this weight above the point. Yeah, that is directed downward as well. But what else is going on? We have pressure. Yep, Force divided by area. What else? As you go down deeper, you get more pressure, because there is more weight above you. Check. So anything else? Well, it would appear that if gravity's strength decreases, should there not be less pressure? Nope. The pressure exerted on any region down there, is a result of the weight above it. Not due to the gravitational force at that depth. It is also balanced as per the 3rd law of motion--An equal, but opposite, reaction for every action. The pressure from above pushes down, and the matter being acted upon pushes back with equal force.

So if you would like to change your stories, again, please, do so, you'll only make yourselves look, well, you know "that word" don't you!

(More so then you already are??)

 

[Brad_Ad23]

But why would I change my story when it is true? As you go down deeper you feel less and less gravity acting on you. The resultant gravity force does indeed become weaker. However, as you do down you also have more mass above you. The more mass above you, the more force it contributes in the opposite direction as that below you, the resultant force thus becomes weaker. The effect this has, is the same as the analogy with the planets crushing you. You have the combined forces acting in two opposite directions. The resultant force vector is zero, however the resultant pressure is not. Why? Because of the laws of motion, and mechanics. You have an equal amount of gravity itself acting around both sides, and an enourmous weight all around. All this mass is trying to pull itself together (since that is what gravity does...it causes stuff to contract). But, at the center, it is equally distributed in all directions. The resultant is no gravity vector. You are correct when saying the gravity energy is still there, yes, it does not go away. However when I have a force of 5 Newtons acting on something from the left, from the right, and from up and down, that particle will not move. What it will feel however, is the resultant force per unit area that the vectors exert on it, also known as pressure. So even though the forces cancel out to the same, the pressure is still there. And remember, pressure from all directions will be equal as well (equal depths same pressure when in equillibrium, which at the center there is).

However, that you say energy compresses matter, that is rather disconcerting to know. Energy in of itself cannot exert a force. Energy may be imparted into something, which MAY cause it to exert a stronger, or weaker force.

And FZ+ is indeed correct. You are measurign the planet's weight in terms of your gravitational field.

Take: F=dp/dt and F = GMm/r².

Let m be the mass of the person and M the mass of the planet. dp/dt is the change in momentum per time interval (you also see this as F=ma, [mdv/dt = dp/dt, and dv/dt = a]). The mutual force of attraction between the two is F = GMm/r².

Now, let us get the acceleration due to gravity of the earth. This case we would be looking for the weight of the person.

ma = GMm/r². small m's go away, and we get:

a = GM/r². The resulting a we get should be roughly 9.8 meters per square second. Plug this into the F = ma equation and we get the weight of the person in Earth's gravity field. But, remember, for every actions there is an equal but opposite reaction. In this case, the changes in momentum must be equal obviously. But one has a large Mass and the other has a small mass. For the momentums to equal, the acceleration, a, ( remember, m dv/dt = dp/dt, and dv/dt = a) one body must have a smaller change in velocity than the other. That body is the earth. This means it is being acted upon by a tiny gravity field. And who's is that? Why the person's! Instead of canceling out the small m, cancel out the big one and find the acceleration. This is the weight of Earth in your gravitational field, which as FZ+ pointed out, you are also weighing. To make this simpler refer to Newton's 3rd law. If you were not exerting equal magnitudes of force, then either A)you would fly into the earth, or B)the Earth would fly into you.


Also, I add that resistence to force is not a vector. You can have a resistive force, or a force of resistance and that will be a vector, but a resistence in of itself to force is no vector.

 

[sol]

http://hyperphysics.phy-astr.gsu.edu/hbase/forces/isq.html#isq

In order for me to see some consistancy here, it was necessary for me to see the logic and develpement of a model of apprehension, based on preceding work done.

Like understanding Euclid's psotulates and then finding his fifth had moved to a different realm. Girolma Saccheri leads us into further thinking.

The logic of this approach must be geometrical defined. Is the metric understood here? I am in need of some education, so if anyone can help, I might help you extend your own knowlegde (logically and geometrically).

Sol