# Where is most "gravity", inside or out?

Discussion in 'Pseudoscience' started by nebel, Feb 29, 2016.

1. ### river

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Yet gravity is the weakest of all forces .

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How do you know?

I mean its science afterall.

And yes certainly the weakest as science has dictated according to the observational evidence, but also as you have been told many times, accumulative also, something you conveniently forget.

5. ### river

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Accumulative gravity , what stores the gravity energy ?

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I have given you links...they are scientific links. clue: It has to do with spacetime geometry, that which you also stupidly reject despite the evidence.

8. ### river

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Thank you, and I'm sure you are capable of reading in the appropriate reputable science threads. Well not really sure, but hey, prove me wrong!

10. ### river

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You have no idea .

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Whatever river...coming from you stuck in with the fringe nonsense, I'll take that as a compliment.

12. ### river

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You shouldn't though . Because it is not a compliment .

13. ### nebel

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Bennu rotates with an equatorial velocity of 32 cm, (1 foot) per second, with a radius of ~ 800 meters. not exactly a force to push you hard against the inner surface, but at the inner surface of the crust, the outwardly pushing centrifugal force would be strongest there, as is the inward pulling strength of the gravitational field, resulting in compacting. bsw. ,
The Yarkovsky effect is increasing the spin, so at some point in the future, the fluff in the middle will join the dense surface to have it all spin apart.

14. ### nebel

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I hope neutralizing means non existing, untraceable, unmeasurable. Floating in zero gravity might be pleasant ( try the barf bomber) having 2 gravities pull in two directions on all atoms in you does not sound re-assuring.
would Einstein say there is no space warp at the the center of a mass? most of the space is warped outside? or most of the warp is outside?

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It means literally that you would be feeling the pull of gravity from all directions and as such neutralized....here are some more explanations that maybe clearer I hope....
https://www.theguardian.com/notesandqueries/query/0,5753,-65124,00.html
Is there any gravity at the centre of the Earth?

Colin Veitch, London, UK
• Yes. There's gravity everywhere - it's an intrinsic property of all matter that has non-zero mass. If you were at the centre of the Earth it would feel like you were weightless. This is because all of the forces on you that result from the Earth's gravity are balanced. Mass attracts mass. There is the same amount of earthly mass in every direction. So you would be pulled equally in each direction and the net force on your body would be zero. This does not mean that there is no gravity at the Earth's centre. There's an awful lot of gravity there!

Mike Burton, Twickenham, UK
• Yes. There is a gravitational atraction between any two objects. If you burrowed to the centre of the earth then you would experience gravity from the surrounding mass of the planet (which would not quite cancel out, as the earth is not a perfect sphere) and also from everything else in the universe (albeit these will be quite small - but remember that the moon's gravity is enough to cause tides at the surface).

• If one assumes the Earth to have uniform mass in each direction from its centre, then a person at the centre would be free of Earth's gravitational force (but not of the graviational force of the sun or other extra-terrestrial bodies).

Jay Weedon, New York, NY, USA
• Of course there is, it's pulling pretty much equally in all directions.

Paul Anderson, Nottingham, England
• You would still feel the gravitational effects of the Sun and other bodies of the Universe, but as far as the Earth's mass goes, at the exact mass centre of the Earth, there is no gravitational attraction from the Earth.

Robert Ward, Leeds, England
• Absolutely. Gravity is everywhere in the Universe. The gravitational forces at the centre of the Earth would be pulling you in all directions, so would effectively cancel out, so that you might not feel a noticeable gravitational pull in any given direction. Also, you would still be experiencing weaker gravitational pull from all other objects in the Universe, which are further away, such as the sun, the moon, the other stars in the galaxy, etc. There's no getting away from it.

• There is indeed gravitational pull at the Earth's centre. But, as the pull is coming from all sides, there is naturally no 'apparent' pull from the place where you are and so it would 'feel' as if there were no gravity at all. The plot of Iain M. Banks novel "The Algebraist" hinges on this very effect.

John Bennett, Glasgow, UK

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Unlike our pretentious anti science fraud river, I support all I say. The above imo would be like balancing a pencil.
The Erath warps spacetime...if you were at the center, you would have all the surrounding mass pulling from all directions, as per Newton. With GR, being at the center, you would still feel the warpage from all directions.
Explained well in this video, particularly at the 4 minute mark. Please listen to the reasons given!

17. ### nebel

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no, i would not be feeling any gravitational pull., because something cancelled does not exist, imho, the opposing warping of spacetime results in a "flat" area near the center.
If literally all matter in me would be tugged in all directions, would I expand*** in a 1 atmosphere cavity in the center of the earth?
*** astronauts,'spine expands during their stay in "zero gravity" but that is not because of the pull of the universe outside, but our bodies propensity to fight the compression on the spine here on the surface.

Last edited: Oct 14, 2020

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Listen to the Professor in the video at the 4 minute mark and the following 1 minute explanation.
And stop being pedantic.

19. ### nebel

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please give us the abstract of that exchange, I am audio impaired.

20. ### nebel

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so: steepness of the slope= warping of spacetime. slope around the center: flat slope at infinity: flat. slope steepest at surface.

Last edited: Oct 14, 2020
21. ### exchemistValued Senior Member

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Sure...from the 4 minute mark, "the force at the center of the Earth is zero....there is no gravity there, specifically, there is no gravitational force. Why is that? Because every chunk of the Earth is pulling on you......I have a chunk of the earth pulling me this way, I have a chunk of the Earth pulling me that way, and a chunk of the Earth pulling me this way, and a chunk pulling me that way, and they all cancel out." being the main gist of what he has to say, concerning our debate.
If some can get the full dialogue for you to read then I welcome it.

23. ### Write4UValued Senior Member

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Consider this:
What happens to you if you fall into a black hole?
https://math.ucr.edu/home/baez/physics/Relativity/BlackHoles/fall_in.html

The intriguing question is, do you stretch because of the gravitational pull or because the spacetime fabric itself stretches and you are part of that matrix?