Understanding gravity

[Cooky]

How is it the gravitational rate of a falling object (9.8 M/sec. Squared), is the same on both the top and bottom side of the earth, when the bottom side sits deeper in earths gravitational well?

IOW, we all know the core of the earth has zero gravity -you would literally float there if you could, and that it is only the bending if the fabric of space that creates "gravity".

...So one side of the earth sits atop the bent space-time. So why do objects fall at the same rate there as at the bottom of the well?

 

[Cooky]

Is there a well on both sides?

 

[Revoltingest]

Is there a well on both sides?

I think there's a problem using a 2 dimensional representation
of a complex 3 (4?) dimensional concept.

 

[Ouroboros]

I think there's a problem using a 2 dimensional representation
of a complex 3 (4?) dimensional concept.

Yup. That's exactly it.

The 2 or 3-D representation of the gravity well is just to give a form of illustration to understand it. In reality, the well is all around in all directions... and it's also around all interacting objects. For instance Earth has a 4-D gravity well, and Luna has one as well, and both are pulling each other. And what's crazy, every person has a slight pull on Earth.

On another note from the OP, the "weight less" thing at the center of Earth is probably not right at all. It's more like equilibrium of gravitational pull from all directions simultaneous.

 

[Polymath257]

The picture you have is a simplification. it essentially gives the 'shape' of the well as you move away from the surface, no matter what direction you are going. The gravitational well itself represents how much energy is required to leave the Earth and get away. So it is pretty much the same everywhere: there is no 'top' or 'bottom' and 'down' is always toward the center of the Earth (for those on the Earth that is).

So, yes, the acceleration due to gravity (9.8 m/s^2) is pretty much the same everywhere on the surface of the Earth. There are minor variations due to things like mountains and whatever is going on under the surface, but those effects are very small compared to that basic 9.8 figure.

If you go to the moon or another planet, however, that acceleration will be different (depending on the mass of the planet and how large the radius is).

 

[Polymath257]

Is there a well on both sides?

All around, actually.

NB: the force of gravity at the center would be zero, but there is still a potential there. The center is at the 'bottom of the well' in every direction.

 

[Polymath257]

On another note from the OP, the "weight less" thing at the center of Earth is probably not right at all. It's more like equilibrium of gravitational pull from all directions simultaneous.

Technically, you would be weightless there. But there is more than one way to describe gravity. The force and the potential are different things (the force is essentially the rate of change of the potential as you move around). So, there is a gravitational potential at the center even though the new force is zero.

 

[PureX]

How is it the gravitational rate of a falling object (9.8 M/sec. Squared), is the same on both the top and bottom side of the earth, when the bottom side sits deeper in earths gravitational well?

IOW, we all know the core of the earth has zero gravity -you would literally float there if you could, and that it is only the bending if the fabric of space that creates "gravity".

...So one side of the earth sits atop the bent space-time. So why do objects fall at the same rate there as at the bottom of the well?

View attachment 35998

You're being fooled by the image. In reality the bending of space is happening in all directions, spherically, all around the Earth. The image is only depicting it via a 2-dimensional plane. AND the image is not meant to be seen as 'a ball resting in a net', and being pulled downward, as you are imagining it, I think.

 

[Terry Sampson]

I think there's a problem using a 2 dimensional representation

Ya think? LOL! Help that boy out!

 

[Salvador]

How is it the gravitational rate of a falling object (9.8 M/sec. Squared), is the same on both the top and bottom side of the earth, when the bottom side sits deeper in earths gravitational well?

IOW, we all know the core of the earth has zero gravity -you would literally float there if you could, and that it is only the bending if the fabric of space that creates "gravity".

...So one side of the earth sits atop the bent space-time. So why do objects fall at the same rate there as at the bottom of the well?

View attachment 35998

 

[Ouroboros]

Technically, you would be weightless there.
But there is more than one way to describe gravity. The force and the potential are different things (the force is essentially the rate of change of the potential as you move around). So, there is a gravitational potential at the center even though the new force is zero.

Ok. Fair enough. The sum of the forces is zero. Which is what I meant with an equilibrium. Gravity doesn't disappear at the center though. You're "weightless" because you're pulled equally in all directions by all mass around you. And that's what I meant. In a way, it's rather that you are completely "weightful".

 

[Salvador]

Do gravitons actually exist as a mass-less, stable, spin-2 particle traveling at the speed of light or are they just a hypothetical concept?

 

[Thief]

How is it the gravitational rate of a falling object (9.8 M/sec. Squared), is the same on both the top and bottom side of the earth, when the bottom side sits deeper in earths gravitational well?

IOW, we all know the core of the earth has zero gravity -you would literally float there if you could, and that it is only the bending if the fabric of space that creates "gravity".

...So one side of the earth sits atop the bent space-time. So why do objects fall at the same rate there as at the bottom of the well?

View attachment 35998

there is no such thing as zero gravity

 

[Salvador]

there is no such thing as zero gravity

Is there such a thing as a "graviton"?

 

[firedragon]

So one side of the earth sits atop the bent space-time. So why do objects fall at the same rate there as at the bottom of the well?

Does one side sit on the space-time continuum? Isnt this just a two dimensional depiction? Or maybe you have another point my capacity doesnt comprehend?

 

[Subduction Zone]

Is there a well on both sides?

That is an attempt to render a four dimensional concept in three dimensions. There is no top or bottom.

 

[It Aint Necessarily So]

How is it the gravitational rate of a falling object (9.8 M/sec. Squared), is the same on both the top and bottom side of the earth,

The earth doesn't have a top or bottom side.

It does have an axis of rotation, which makes the poles privileged positions, but neither pole is at the top or bottom of the earth. This map is just as valid as the one we're used to:

As others have noted, your graphic mislead you. You saw a sphere on a trampoline. Other illustrations provided here hopefully showed you that there is no top to the earth.

 

[Skwim]

How is it the gravitational rate of a falling object (9.8 M/sec. Squared), is the same on both the top and bottom side of the earth, when the bottom side sits deeper in earths gravitational well?

IOW, we all know the core of the earth has zero gravity -you would literally float there if you could, and that it is only the bending if the fabric of space that creates "gravity".

...So one side of the earth sits atop the bent space-time. So why do objects fall at the same rate there as at the bottom of the well?

View attachment 35998

Think of the strength divided into discrete concentric spheres encompassing the planet.

.
.

 

[Heyo]

Do gravitons actually exist as a mass-less, stable, spin-2 particle traveling at the speed of light or are they just a hypothetical concept?

The "graviton" is not part of the Standard Model. Particle physicists have practically abandoned the idea of a graviton. The GR model explains gravity well enough.

 

[Polymath257]

Do gravitons actually exist as a mass-less, stable, spin-2 particle traveling at the speed of light or are they just a hypothetical concept?

At this point gravitons have not been detected. They are the expected quantum particle for gravity.