Gravity at the center of the Earth?

Anyone saying that pressure is low at the center of the Earth has a high bar to jump over. At what point does the pressure start decreasing again and why? The mathematics of pressure increase is well understood and accurate. Go down to the bottom of the sea in a wetsuit instead of a bathysphere if you don't believe pressure increases as you go deeper.

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"I think about how we are stucked to the earths crust is the anticlockwise motion of this earth and all forces due to Earths anti motion let us to stand on the ground."
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Hello again,
I am still not satisfied and what are you all talking here about the PRESSURE plz let me know,
and I m giving you here another assumption about what I think about the Gravity.
Assumption:
assume that the the Sphere of earth where we can see these these moving clouds and consider also that the sphere is also moving in anticlockwise direction.
case1: Place a block of wood on(above) the sphere1.
case2: Place a block of wood inside(below) of the sphere1.

Then tell me what dose the centripital & Centrifugal forces, forming due to Sphere1(earth) rotation throw this block of wood in which direction in case1 and case2.

I will be very thankfull to you If you pay attention towards this assumption.
Thankyou very much.
Zain Abbas

I have everything in mind so confusive about the natural facts.

Jeremy, You ask good questions and I'm glad you do so. The reason pressure rises is because mass per unit of area increases-right? So, in a sphere the mass tends to be greater near the surface-right? 50% of the mass of a sphere is in the outer 20% of its radius. The mass is the home of gravity force and since 50% of the mass is in the outer shell of the sphere 50% of the gravity force is also there. 50% of the gravity force is opposing the opposite 50% that is inside the sphere.(I hope this is not too confusing) So the max gravity is at the interface of the two spheres. Gravity being the force underlying pressure it follows that pressure is greatest somewhere near the interface of the two spheres and falls off as you go deeper to the mass center. Draw the two spheres and do the math and you aggree.

Jim, I agree with your assessment of the mass distribution in the sphere, however; I assert that the core could be compressed gases and actually have a higher density. Your mass distribution only holds if density is constant throughout. I imagine a structure where the mass of the solid and liquids above supercompresses a core of hydrogen gases. An example of this is Jupiter whose atmosphere is so dense that penetrance by even a solid is difficult. We know that jupiter is ~ 90% H2(g). Even with best research on Earth we are uncertain of even the state of matter let alone the composition of the mantle let alone the core. Maybe we shouldnt drill too far, might make a gas jet and crack the planet

Mark Vitrone

The general tendancy is for more dense materials to settle downward.

Jupiter infact is believed to have diamonds in its core. I just saw that within this past year. (as well as one of the other gas giants, I forget which one.)

Wouldnt mind having a transporter for the Jupiter core then. I could put DeBeers right out of business...<img src=icon_smile_evil.gif border=0 align=middle>

Mark Vitrone