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Quickshift
2008-Sep-29, 09:33 PM
Ok this is my first thread post so be gentle. My question may be suited for the ATM so forgive me if I'm in error.

Gravity has always been accepted as a pulling motion toward an object with mass.
We have all seen the annimations of a mass distorting the space time fabric creating a gravity field on a 2d surface. Would it look more like an olive sandwhich? lol
What if--
space time is a fabric that is woven tight but the weaves are spaced further apart around and through the object creating a path of least resistance?



My question is, would it be possible that gravity
is a pushing motion of the fabric of space / time against the mass that forces unconnected objects to the mass's center core which is the point of less space / time resistance?

My calculus is poor so I may not understand your answers
Thanks
Quickshift

spratleyj
2008-Sep-29, 10:08 PM
Ok this is my first thread post so be gentle. My question may be suited for the ATM so forgive me if I'm in error.

Gravity has always been accepted as a pulling motion toward an object with mass.
We have all seen the annimations of a mass distorting the space time fabric creating a gravity field on a 2d surface. Would it look more like an olive sandwhich? lol
What if--
space time is a fabric that is woven tight but the weaves are spaced further apart around and through the object creating a path of least resistance?



My question is, would it be possible that gravity
is a pushing motion of the fabric of space / time against the mass that forces unconnected objects to the mass's center core which is the point of less space / time resistance?

My calculus is poor so I may not understand your answers
Thanks
Quickshift

So are you asking if gravity is "spacetime" pushing objects towards other object's center of gravity?

If that is what your asking then I think you may be thinking of the rubber sheet analogy... in which masses bend spacetime... however as with most analogies it has it's flaws...

undidly
2008-Sep-29, 10:13 PM
Ok this is my first thread post so be gentle. My question may be suited for the ATM so forgive me if I'm in error.

Gravity has always been accepted as a pulling motion toward an object with mass.
We have all seen the annimations of a mass distorting the space time fabric creating a gravity field on a 2d surface. Would it look more like an olive sandwhich? lol
What if--
space time is a fabric that is woven tight but the weaves are spaced further apart around and through the object creating a path of least resistance?



My question is, would it be possible that gravity
is a pushing motion of the fabric of space / time against the mass that forces unconnected objects to the mass's center core which is the point of less space / time resistance?

My calculus is poor so I may not understand your answers
Thanks
Quickshift

Gravity is an effect NOT a force.
I dare not explain here because it may be seen as ATM.
Your fabric of space / time idea is almost right.

01101001
2008-Sep-29, 10:25 PM
Welcome.


Ok this is my first thread post so be gentle. My question may be suited for the ATM so forgive me if I'm in error.
[...]
My question is, would it be possible that gravity
is a pushing motion [...]

If you want to read about "pushing gravity", head to ATM and see the idea time and time again not presented persuasively in the face of more sensical mainstream physics.

For instance:
Does gravity push or pull ? (http://www.bautforum.com/against-mainstream/50294-does-gravity-push-pull.html)
Graviton - pushing theory osf gravity (http://www.bautforum.com/against-mainstream/27005-graviton-pushing-theory-osf-gravity.html)
Pushing Gravity (http://www.bautforum.com/against-mainstream/934-pushing-gravity.html)
Pushing gravity as the result of the Pull. (http://www.bautforum.com/against-mainstream/14817-pushing-gravity-result-pull.html)
Gravity Behaving BADLY (http://www.bautforum.com/against-mainstream/13695-gravity-behaving-badly.html)

And so on...

spratleyj
2008-Sep-30, 12:28 AM
If you're asking "does gravity push or pull?" The answer is it can do both... however it may only "push" at extreme condidtions...

Quickshift
2008-Sep-30, 02:30 AM
I believe my question was understood. I'm of the thinking if we understood the source of gravity more it would be a key to unheard of space flight.
I'm interested in the flaws of the rubbersheet analogy. I'll go to the ATM like suggested and see what is in there also.
Thanks

Jeff Root
2008-Sep-30, 03:24 AM
All analogies are flawed. A few properties of stretchy rubber sheets
work just fine to convey certain aspects of how gravity works. Most
are completely irrelevant. The problem is when someone mistakes an
irrelevant feature for a relevant one. An example of that might be to
wonder if spacetime can be stretched so much that it rips.

-- Jeff, in Minneapolis

Woot!
2008-Sep-30, 03:01 PM
Is there really an observable difference between the two? Or is this a version of the old question about whether zebras are black with white stripes or white with black stripes?

loglo
2008-Sep-30, 03:41 PM
The observable difference is that no-one has presented a pushing gravity theory that reflects observations or makes accurate predictions.

hhEb09'1
2008-Sep-30, 07:23 PM
Is there really an observable difference between the two? Or is this a version of the old question about whether zebras are black with white stripes or white with black stripes?I'm with you Woot!, when I read the OP, I didn't see much difference from the usual spacetime interpretation. If spacetime impells in the fashion as is generally accepted, is it a push or a pull? It looks to me like that is the distinction asked by the OP.

undidly
2008-Oct-10, 06:52 AM
I'm with you Woot!, when I read the OP, I didn't see much difference from the usual spacetime interpretation. If spacetime impells in the fashion as is generally accepted, is it a push or a pull? It looks to me like that is the distinction asked by the OP.

A push compresses the pushed object because the force is strongest on the side nearest to the force.
A pull stretches the pulled object for the same reason.

A globule of water in an orbiting space ship is very slightly pointed at the bottom ( the side toward the Earth )because gravity is stronger on the bottom.

Satellites using gravity gradient stabilization depend on this effect.
Gravity PULLS the bottom more than the top.

hhEb09'1
2008-Oct-10, 11:20 AM
A push compresses the pushed object because the force is strongest on the side nearest to the force.
A pull stretches the pulled object for the same reason.That kinda makes sense, as a definition, but gravity is a body force (or, a spacetime effect on the entire body), not just on one side.
Gravity PULLS the bottom more than the top.Depends upon the context. In some configurations, gravity pulls the top more than the bottom, or as you would say, pushes.

But that's the point, as Woot! said, in the context of the OP there is no real distinction. It can be either, even using your definition. We're not talking about the various "pushing gravity" theories here.

undidly
2008-Oct-11, 02:04 AM
That kinda makes sense, as a definition, but gravity is a body force (or, a spacetime effect on the entire body), not just on one side.Depends upon the context. In some configurations, gravity pulls the top more than the bottom, or as you would say, pushes.

But that's the point, as Woot! said, in the context of the OP there is no real distinction. It can be either, even using your definition. We're not talking about the various "pushing gravity" theories here.

^In some configurations, gravity pulls the top more than the bottom, or as you would say, pushes.^

I said top only in reference to things near to Earth meaning the side furthest from the Earth.

In what configuration does gravity pull the top (furthest side ) MORE than the bottom (nearest side?.
Can't be right.Many things would not be the way they are.
I look forward the a more detailed explanation.

hhEb09'1
2008-Oct-11, 03:28 AM
In what configuration does gravity pull the top (furthest side ) MORE than the bottom (nearest side?.
Can't be right.Many things would not be the way they are.
I look forward the a more detailed explanation.Take the same globule of water and bury it in a cavity on Mars. As we've discussed in another thread, the gravity on Mars probably decreases as the depth increases, so the force of gravity would be less on the bottom.

mugaliens
2008-Oct-13, 07:18 PM
Would it look more like an olive sandwhich? lol

Only after the bread has been mashed into paper by the heel of one's hand!

cjameshuff
2008-Oct-13, 08:29 PM
Take the same globule of water and bury it in a cavity on Mars. As we've discussed in another thread, the gravity on Mars probably decreases as the depth increases, so the force of gravity would be less on the bottom.

For a more extreme version place it in a small hole (small enough for its own gravitational effects to be negligible) in a large spherical shell. The portion inside the shell will feel no gravity, the portion outside will feel the full force.

Start it entirely in the interior and give it a nudge toward the hole. It'll coast at a constant speed (assuming no atmospheric drag), start decelerating as it emerges from the sphere, reverse direction, and fall back toward the sphere, either falling back through the hole at the same speed it was pushed outward at, or splattering against the outside surface of the shell.

undidly
2008-Oct-14, 07:47 AM
For a more extreme version place it in a small hole (small enough for its own gravitational effects to be negligible) in a large spherical shell. The portion inside the shell will feel no gravity, the portion outside will feel the full force.

Start it entirely in the interior and give it a nudge toward the hole. It'll coast at a constant speed (assuming no atmospheric drag), start decelerating as it emerges from the sphere, reverse direction, and fall back toward the sphere, either falling back through the hole at the same speed it was pushed outward at, or splattering against the outside surface of the shell.

^or splattering against the outside surface of the shell.^
Yes if the shell is spinning,cannot return if the hole has moved.

After the globule passes through the hole it decelerates and returns towards the shell but the question is, does gravity PULL it back or PUSH it back.

My conclusion that gravity gradient deformation of the globule proves that
gravity pulls and not pushes is wrong.

hhEb09'1 has really made me think about this.

Does my vacuum cleaner suck (pull ) or does air pressure push the dust.
Must be push as will not work without air.

If gravity pulls or causes a push is that a pull or push of what?.Aether ?.

mugaliens
2008-Oct-14, 03:12 PM
After the globule passes through the hole it decelerates and returns towards the shell but the question is, does gravity PULL it back or PUSH it back.

The convention used is "pull," as there is nothing on the rear side that could push.


My conclusion that gravity gradient deformation of the globule proves that
gravity pulls and not pushes is wrong.

Interesting conclusion. However, you are incorrect.


Does my vacuum cleaner suck (pull ) or does air pressure push the dust.
Must be push as will not work without air.

Yet gravity works without air...

max8166
2008-Oct-14, 03:59 PM
I have always considered it to be the pull of gravity however gravity is a strange thing indeed. The explanation of a bend in spacetime (http://en.wikipedia.org/wiki/Spacetime) makes most people say "what does that mean?" and reach for another drink!

But what it means is that gravity neither pulls nor pushes it just is.

cjameshuff
2008-Oct-14, 05:18 PM
My conclusion that gravity gradient deformation of the globule proves that
gravity pulls and not pushes is wrong.

It's not one of the arguments I've heard. Mostly the problems with push gravity have to do with things like the "push" particles needing to collide inelastically, thus accumulating in matter, the heating that all those collisions will produce, and the drag that moving objects would experience. Similar effects can produce attractive forces in microscopic systems, though, it just doesn't work as an explanation for gravity.

tonybaloney
2008-Oct-14, 06:05 PM
I have a gravity question in regards to this new "Dark Flow" phenomenon recently discovered.

If gravity, in fact, travels at the speed of light as I have read, how is it possible that we can detect effects of this elusive gravity source pulling on masses in the universe that we can observe yet we cannot actually observe it because it is outside of our field of observation?

cjameshuff
2008-Oct-14, 08:24 PM
I have a gravity question in regards to this new "Dark Flow" phenomenon recently discovered.

If gravity, in fact, travels at the speed of light as I have read, how is it possible that we can detect effects of this elusive gravity source pulling on masses in the universe that we can observe yet we cannot actually observe it because it is outside of our field of observation?

I don't know that this is the answer, but one possible explanation is that those further sources are directly visible (or at least, their past is), just too dim and red-shifted for us to see and tell apart from the background with current instruments.

tonybaloney
2008-Oct-14, 10:05 PM
With something as massive as what is required to cause this pull detected, you would think there would not be any question as to whether we can see it or not. We should see it and it should be huge.

If you ask me, I think that this dark flow is a little bit of a shaky finding.

Felix Ibe
2008-Oct-15, 09:44 AM
what is the name of the force that moves a rocket?

Neverfly
2008-Oct-15, 09:49 AM
what is the name of the force that moves a rocket?

I'm not sure if this is what you're asking, But I'd simply call it Newtons 2nd law (http://en.wikipedia.org/wiki/Newton%E2%80%99s_laws_of_motion#Newton.27s_second_ law:_law_of_resultant_force).

Felix Ibe
2008-Oct-15, 09:49 AM
has man evre visited planet mars if no why?

Neverfly
2008-Oct-15, 09:54 AM
:neutral:


What....?Bot?

cjameshuff
2008-Oct-15, 02:53 PM
With something as massive as what is required to cause this pull detected, you would think there would not be any question as to whether we can see it or not. We should see it and it should be huge.

It's literally behind the microwave background, by my understanding. The flow, if it proves to be real, was created before the universe expanded and cooled enough to become transparent...that mass concentration moved outside our observable universe before that time, and so the background we see is actually red-shifted glow from nearer parts of space. Unlike light, gravity was not obscured during the earlier time, and so we see the gravitational effects of a mass concentration that we can't see directly.

tonybaloney
2008-Oct-15, 04:45 PM
Cjameshuff - so are you basically saying (in my naiive terms) that there is no light emanating from the huge masses of material that is causing this dark flow, if it proves to be real? In other words the source of the pull of gravity on the objects in the observable universe has not matured enough to allow star formation, etc. I'm sure this is an incorrect assumption of what you are saying, but please help me understand.

Also, if this is the case - it makes it sound like all of the matter that is apparently being affected by this dark flow is so close to the edge of the observable universe (and early in the universe) so that it can be affected by this unknown source of gravity. However it states in the finding that this observable matter is only 6 billion light years away (only halfway to the edge of the universe).

cjameshuff
2008-Oct-15, 05:30 PM
Cjameshuff - so are you basically saying (in my naiive terms) that there is no light emanating from the huge masses of material that is causing this dark flow, if it proves to be real? In other words the source of the pull of gravity on the objects in the observable universe has not matured enough to allow star formation, etc. I'm sure this is an incorrect assumption of what you are saying, but please help me understand.

Not that there was no light being given off, just that the light didn't get anywhere. If we were closer, we might see it as a brighter area in the microwave background (which is very nearly perfectly homogenous), and if closer still, perhaps an unusually high density of galaxy clusters.



Also, if this is the case - it makes it sound like all of the matter that is apparently being affected by this dark flow is so close to the edge of the observable universe (and early in the universe) so that it can be affected by this unknown source of gravity. However it states in the finding that this observable matter is only 6 billion light years away (only halfway to the edge of the universe).

Recall that the velocity gained when the universe was more compact and the dense region was closer would not disappear. And the effect is not very big...which is the reason for the controversy. It takes careful analysis to detect, and it would be easy to get that analysis wrong.

Felix Ibe
2008-Oct-17, 02:33 PM
why is it that without the electro-magetic force there would be no life?

Felix Ibe
2008-Oct-17, 02:40 PM
via my research i have discovered the answer to my question 'what is the force that move a rocket' i went on such research to help make it known to some new and probably old members of this forum. the force according to my reseach is the CENTRIFUGAL FORCE

cjameshuff
2008-Oct-17, 04:34 PM
why is it that without the electro-magetic force there would be no life?

Rather off topic for this thread...but there would be no light and no atoms. Maybe other forces could produce an equivalent, but it wouldn't be life "as we know it".



via my research i have discovered the answer to my question 'what is the force that move a rocket' i went on such research to help make it known to some new and probably old members of this forum. the force according to my reseach is the CENTRIFUGAL FORCE

That's an...interesting conclusion. How about starting a new thread explaining it, though? Including explaining why you think it is so.

HenrikOlsen
2008-Oct-17, 05:33 PM
That's an...interesting conclusion. How about starting a new thread explaining it, though? Including explaining why you think it is so.
But he should do so in ATM, not here, as it's a wildly non-standard idea.