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From: clipka
Subject: Gravitation
Date: 17 Oct 2015 22:44:38
Message: <56230796$1@news.povray.org>
Einstein's General Theory of Relativity is nearly a hundred years old by
now, but I think it is only now, in the age of YouTube, that a
fundamental understanding starts seeping into common knowledge of what
the theory /really/ means.

For instance, according to the General Theory of Relativity,
gravitational pull is caused by the curvature of spacetime. That's what
it says, isn't it? Right?

Err... nope.

What the General Theory of Relativity /really/ says is that there is /no
such thing/ as gravitational pull. To the contrary: What really makes
you stick to the ground is not a force pushing /you/ /down/, but a force
pushing /the ground/ /up/. More specifically, the electromagnetic forces
between the atoms of the earth push it apart with such a force that the
ground races upward at an acceleration of 9.81 m/s^2 - and all the while
the fabric of space near and at earth just contracts at an equivalent
rate, shriveling like the surface of a punctured balloon, so that the
effective distance between the atoms never gets any bigger despite their
accelerated motion through space.

I had been pondering this for a few days now, when I stumbled across
this video which I think gets the idea across quite well:

https://youtu.be/NblR01hHK6U


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From: Stephen
Subject: Re: Gravitation
Date: 18 Oct 2015 02:03:19
Message: <56233627@news.povray.org>
On 10/18/2015 3:44 AM, clipka wrote:
> Einstein's General Theory of Relativity is nearly a hundred years old by
> now, but I think it is only now, in the age of YouTube, that a
> fundamental understanding starts seeping into common knowledge of what
> the theory /really/ means.
>
> For instance, according to the General Theory of Relativity,
> gravitational pull is caused by the curvature of spacetime. That's what
> it says, isn't it? Right?
>
> Err... nope.
>
> What the General Theory of Relativity /really/ says is that there is /no
> such thing/ as gravitational pull. To the contrary: What really makes
> you stick to the ground is not a force pushing /you/ /down/, but a force
> pushing /the ground/ /up/. More specifically, the electromagnetic forces
> between the atoms of the earth push it apart with such a force that the
> ground races upward at an acceleration of 9.81 m/s^2 - and all the while
> the fabric of space near and at earth just contracts at an equivalent
> rate, shriveling like the surface of a punctured balloon, so that the
> effective distance between the atoms never gets any bigger despite their
> accelerated motion through space.
>
> I had been pondering this for a few days now, when I stumbled across
> this video which I think gets the idea across quite well:
>
> https://youtu.be/NblR01hHK6U
>


So we should think that instead of the Earth attracting the apple with a 
force of, say, 1.0 N. The apple attracts the Earth with a force of 
5.86E+25 N. Makes sense.

You know, I find it hard to give any credence to someone who talks so 
fast. A sure sign that they are trying to put one over on you. IMO

Mass of an "average" apple = 0.102 Kg
http://hypertextbook.com/facts/2004/WaiWingLeung.shtml

Mass of the Earth = 5.97E+24 Kg
(Google)




-- 

Regards
     Stephen


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From: Stephen
Subject: Re: Gravitation
Date: 18 Oct 2015 02:12:36
Message: <56233854$1@news.povray.org>
On 10/18/2015 7:03 AM, Stephen wrote:
> The apple attracts the Earth with a force of 5.86E+25 N. Makes sense.

Woops! I forgot to mention inertia. :-(


-- 

Regards
     Stephen


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From: clipka
Subject: Re: Gravitation
Date: 18 Oct 2015 05:05:22
Message: <562360d2$1@news.povray.org>
Am 18.10.2015 um 08:03 schrieb Stephen:
> On 10/18/2015 3:44 AM, clipka wrote:
>> Einstein's General Theory of Relativity is nearly a hundred years old by
>> now, but I think it is only now, in the age of YouTube, that a
>> fundamental understanding starts seeping into common knowledge of what
>> the theory /really/ means.
>>
>> For instance, according to the General Theory of Relativity,
>> gravitational pull is caused by the curvature of spacetime. That's what
>> it says, isn't it? Right?
>>
>> Err... nope.
>>
>> What the General Theory of Relativity /really/ says is that there is /no
>> such thing/ as gravitational pull. To the contrary: What really makes
>> you stick to the ground is not a force pushing /you/ /down/, but a force
>> pushing /the ground/ /up/. More specifically, the electromagnetic forces
>> between the atoms of the earth push it apart with such a force that the
>> ground races upward at an acceleration of 9.81 m/s^2 - and all the while
>> the fabric of space near and at earth just contracts at an equivalent
>> rate, shriveling like the surface of a punctured balloon, so that the
>> effective distance between the atoms never gets any bigger despite their
>> accelerated motion through space.
>>
>> I had been pondering this for a few days now, when I stumbled across
>> this video which I think gets the idea across quite well:
>>
>> https://youtu.be/NblR01hHK6U
>>
> 
> 
> So we should think that instead of the Earth attracting the apple with a
> force of, say, 1.0 N. The apple attracts the Earth with a force of
> 5.86E+25 N. Makes sense.

No, no - not at all.

What happens is that Earth, by virtue of having mass, gobbles up space
inside and around it. Always. Constantly. Whether there are any apples
out there or not. (So does the apple, but that's negligible compared to
Earth's dietary budget.) There's no acceleration or even movement
involved there /per se/ - in the vicinity of matter, distances just
shrink over time. Fast.

If it was only for this mechanism, earth would shrivel to nothingness in
a matter of... minutes? hours? Dunno, but certainly in less than a day.
Space between the elementary particles would just shrink to zero.

Fortunately, electromagnetic force comes to our rescue: The electron
clouds of any two atoms in the universe repel each other. Partially this
is compensated by the fact that the electron clouds of any atom  in the
universe also attracts the nucleus of any other atom, but on average the
net EM force is repelling. And there are a lot of atoms in the Earth. So
the atoms making up earth constantly accelerate away from each other.
Earth is exploding.

Now while this seems even more bad news, it is important to note that
the repelling EM force heavily depends on the distance between the
atoms, much more so than the space-gobbling mechanism does. So while
space is busy shriveling away and Earth is busy exploding within this
space, these two mechanisms have long reached an equilibrium: The
distance between Earth's center and its surface is constant (save for
some other minor effects, such as Earth accreting more solid material
and evaporating light gases such as Helium).

But even though Earth's radius is constant, Earth's surface still /does/
accelerate upward. Not because it is attracted by apples out there, mind
you - to the contrary: Earth and the dropping apple /repel/ each other.
A tiny bit. But much more so, Earth is repelling itself, and hurtles
onward towards the unsuspecting dropping apple - until the two come so
close that EM forces between Earth and the apple suddenly skyrocket, and
(after a bit of bouncing around) come into equlibrium with the collapse
of space. The apple now races outwards along with Earth's surface.

Whoosh.

We're riding an explosion that is the only thing standing between us and
the formation of a black hole.


Also, think of this: If you throw an apple, it moves through space in a
/straight/ line - any apparent curvature of its trajectory is due to
Earth's surface constantly accelerating upwards. Not towards the apple
but away from Earth's center. In a lump of space that's busy shrinking.


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From: Thomas de Groot
Subject: Re: Gravitation
Date: 18 Oct 2015 07:30:33
Message: <562382d9$1@news.povray.org>
The application of Ockams's razor tells me that this is not correct.

I shall be more inclined to consider the day Roger Penrose confirms ;-)

-- 
Thomas


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From: nemesis
Subject: Re: Gravitation
Date: 18 Oct 2015 10:10:01
Message: <web.5623a77031b6578794c8e9160@news.povray.org>
I like that idea, as batshit crazy as it sounds.  Riding an explosion away from
a black hole is poetic imagery at its finest.

But wait.  Isn't the fabric of spacetime itself expanding and accelerating?
Perhaps our little muddy black hole chomps so much of ut away that it remains
constant in the vicinity...

oh well, I always hoped dinos back then would be today as small as a chicken,
aside from their by now equally expanded skeletons...


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From: Stephen
Subject: Re: Gravitation
Date: 18 Oct 2015 10:29:19
Message: <5623acbf$1@news.povray.org>
>>  Makes sense.
>
> No, no - not at all.
>

Sorry, I was in a rush and forgot the "Like Hell it does" icon.


> What happens is that Earth, by virtue of having mass, gobbles up space
> inside and around it. Always. Constantly. Whether there are any apples
> out there or not. (So does the apple, but that's negligible compared to
> Earth's dietary budget.) There's no acceleration or even movement
> involved there /per se/ - in the vicinity of matter, distances just
> shrink over time. Fast.
>
> If it was only for this mechanism, earth would shrivel to nothingness in
> a matter of... minutes? hours? Dunno, but certainly in less than a day.
> Space between the elementary particles would just shrink to zero.
>
> Fortunately, electromagnetic force comes to our rescue: The electron
> clouds of any two atoms in the universe repel each other. Partially this
> is compensated by the fact that the electron clouds of any atom  in the
> universe also attracts the nucleus of any other atom, but on average the
> net EM force is repelling. And there are a lot of atoms in the Earth. So
> the atoms making up earth constantly accelerate away from each other.
> Earth is exploding.
>

To my untutored eyes* that sounds* like stability.

Getting my metaphors a bit mixed. I know.

> Whoosh.
>
> We're riding an explosion that is the only thing standing between us and
> the formation of a black hole.
>

An explosion with an average velocity of 0 m/s?
Scary.

>
> Also, think of this: If you throw an apple, it moves through space in a
> /straight/ line - any apparent curvature of its trajectory is due to
> Earth's surface constantly accelerating upwards. Not towards the apple
> but away from Earth's center. In a lump of space that's busy shrinking.
>

If you say so. But consider using another inertial frame of reference. 
One that contains both the Earth and the apple. Which object, the Earth 
or the apple, travels a greater distance in the same time frame?
I hazard a guess that it will be the apple that has the greater velocity 
and thus acceleration.

Sorry, I wuz an enjuneer.

-- 

If you eat chocolate that you did not want to eat. Then it does not 
count as chocolate.

Sir Terry P.


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From: scott
Subject: Re: Gravitation
Date: 19 Oct 2015 03:18:55
Message: <5624995f$1@news.povray.org>
> What happens is that Earth, by virtue of having mass, gobbles up space
> inside and around it. Always. Constantly. Whether there are any apples
> out there or not. (So does the apple, but that's negligible compared to
> Earth's dietary budget.) There's no acceleration or even movement
> involved there /per se/ - in the vicinity of matter, distances just
> shrink over time. Fast.
>
> If it was only for this mechanism, earth would shrivel to nothingness in
> a matter of... minutes? hours? Dunno, but certainly in less than a day.
> Space between the elementary particles would just shrink to zero.
>
> Fortunately, electromagnetic force comes to our rescue: The electron
> clouds of any two atoms in the universe repel each other. Partially this
> is compensated by the fact that the electron clouds of any atom  in the
> universe also attracts the nucleus of any other atom, but on average the
> net EM force is repelling. And there are a lot of atoms in the Earth. So
> the atoms making up earth constantly accelerate away from each other.
> Earth is exploding.

If gravity (or rather, mass) causes space to contract and get gobbled 
up, this must mean then that EM forces (and other equations?) must 
somehow be able to measure distances "outside" of this distorted and 
gobbled up space? There must be an external "real" space that is somehow 
related to the distored spacetime by the distribution of mass around.


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From: clipka
Subject: Re: Gravitation
Date: 19 Oct 2015 10:06:35
Message: <5624f8eb@news.povray.org>
Am 18.10.2015 um 16:29 schrieb Stephen:

>> Also, think of this: If you throw an apple, it moves through space in a
>> /straight/ line - any apparent curvature of its trajectory is due to
>> Earth's surface constantly accelerating upwards. Not towards the apple
>> but away from Earth's center. In a lump of space that's busy shrinking.
>>
> 
> If you say so. But consider using another inertial frame of reference.
> One that contains both the Earth and the apple. Which object, the Earth
> or the apple, travels a greater distance in the same time frame?
> I hazard a guess that it will be the apple that has the greater velocity
> and thus acceleration.

Whatever frame of reference you choose - if it is truly inertial, you'll
always find the apple (while airborne) moving at constant velocity (or
remaining at rest, which is a special case thereof), and Earth's surface
accelerating radially from its center at 9.81 m/s^2. (As long as you
ignore aerodynamic drag and remain sufficiently close to Earth's surface
and the apple, that is.)

(Hint: What makes a frame of reference inertial? The fact that it
doesn't accelerate. How can you test it? By releasing some item with an
initial velocity of v=0 relative to the frame of reference, and
verifying that the item remains stationary. If you like, do the
experiment inside an elevator cabin with no windows.)


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From: clipka
Subject: Re: Gravitation
Date: 19 Oct 2015 10:14:03
Message: <5624faab@news.povray.org>
Am 19.10.2015 um 09:18 schrieb scott:

> If gravity (or rather, mass) causes space to contract and get gobbled
> up, this must mean then that EM forces (and other equations?) must
> somehow be able to measure distances "outside" of this distorted and
> gobbled up space? There must be an external "real" space that is somehow
> related to the distored spacetime by the distribution of mass around.

No, there's no need for any "meta-space". In the vicinity of any mass,
EM forces still propagate according to Maxwell's wave equations through
whatever space is there at the very moment the wavefront traverses it.

Which is exactly why light appears to "bend" around massive objects.


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