Re: The antics of thermodynamics, the depravity of relativity, the bunkum of quantum

On Mon, 10 Mar 2025 19:54:55 +0000, jerryfriedman wrote:

On Sun, 9 Mar 2025 9:50:06 +0000, Peter Moylan wrote:
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On 09/03/25 09:58, Phil wrote:

On 08/03/2025 22:46, Bertietaylor wrote:

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It's just as implausible as the suggestion (easily disproved)
that the pressure is zero at the centre of the earth.

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The pressure is most certainly zero at the centre of the stars
and planets. Read a first year book on physics.

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Which will say that within an enclosed surface with mass the net
gravitational force or pressure is zero.

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Read that first year book yourself. Did you find the words "or
pressure"? No, I didn't think so. You've tried to conclude something
about the pressure from the gravitational force. That doesn't work,
because they are different quantities.
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Gravitational force, like all forces, is a vector quantity. It has a
magnitude and a direction. That makes it possible that a number of
nonzero vectors can sum to zero; and, indeed, that is what happens
inside a spherical shell.
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Pressure is a scalar. If you add two pressures, you get a higher
pressure. There's no such thing as a negative pressure to cancel out the
first pressure.
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Think of a cone, or similar shape, whose point is at the centre of the
earth. You can separate out a section with thickness dr, and write down
the force balance equation for that slab. (This, too, is first year
physics.) From that you get a differential equation for the pressure as
a function of radius. No matter what simplifications you make, you will
get the same conclusion: the deeper you go, the higher the pressure.
Which is something that ocean divers can confirm from their own
experience.

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Even swimming pool divers.
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At the centre of the earth, the gravitational force is zero but the
pressure is at a maximum.
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Presumably, by an analogous argument, the pressure at the centre of a
 balloon is also zero?

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Actually, the gravitational force at the centre of a balloon is zero, if
you count only the force due to the balloon itself. But of course, you
do have to count the attraction from the earth as well.
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Either way, what you conclude about the gravitational force says nothing
about the pressure. They're different quantities.

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They're different, but they are connected.  Since
the gravitational force at the center of the Earth is
0,

Good. So there is NO force in the centre of any star causing pressure,
compression, heat, fusion of hydrogen then outward radiation - as
presently accepted globally.
As pressure is force divided by area there cannot be pressure where
force is zero.
No neutron stars, no black holes, no big bang, etc.
you can conclude that the pressure /gradient/

there is 0.  Hint to Arindam.

The pressure along a line from the surface to the centre of star or
planet varies from zero to a peak and then to zero. Such is the pressure
gradient within stars and planets.
Such is the insight of Arindam as he published online several years ago.
When the not terminally brainwashed learn this they may if they also
have courage pay Arindam to lecture at good places, and publish his
works.
Not holding our breaths!
Woof woof woof-woof woof
Bertietaylor

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Jerry Friedman
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